FSRH Guideline
Combined Hormonal Contraception

January 2019 (Amended October)320| FSRH

Faculty of Sexual & Reproductive Healthcare (FSRH) provided funding to the Clinical Effectiveness
Unit (of the FSRH) to assist them in the production of this guideline,
Combined Hormonal Contraception (January 2019, amended October 2023).
Published by the Faculty of Sexual & Reproductive Healthcare.
Registered in England No. 2804213 and Registered Charity No. 1019969
Combined Hormonal Contraception first published in October 2011.
Copyright © Faculty of Sexual & Reproductive Healthcare January 2019.
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January 2019.
Published in the UK.
From January 2019 the FSRH has published its electronic clinical guidelines on both its own
website (www.fsrh.org.uk) and as an electronic supplement to the BMJ Sexual & Reproductive
Health (BMJ SRH) journal. The guidelines have the same content. If a guideline is updated, the
FSRH replace the version on its website and the BMJ Sexual & Reproductive Health (BMJ SRH)
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The digital version can be accessed from the BMJ SRH website: FSRH Guideline (January 2019,
amended October 2023) Combined Hormonal Contraception. BMJ Sexual & Reproductive Health
2019; 45:Suppl 1. http://dx.doi.org/10.1136/bmjsrh-2018-CHC

NICE has accredited the process used by the Faculty of Sexual & Reproductive Healthcare
to produce this guideline. More inf ormation on accreditation can be viewed at www.nice.org.uk/
accreditation.

FSRH guideline: CHC

Abbreviations used
ATE
BMD
BMI
CEU
CHC
COC
CTP
CVR
DRSP
DVT
EC
EE
FSH
FSRH
GDG
hCG
HCP
HFI
HMB
HR
HRT
HSUPT
IRR
IUS
LARC
LH
LNG
MI
NET
NICE
OC
PCOS
PMDD
PMS
POP
RCOG
RCT
RR
STI
UKMEC
UPA
UPSI
VTE
WHO

arterial thromboembolism
bone mineral density
body mass index
Clinical Effectiveness Unit
combined hormonal contraception/contraceptive
combined oral contraception/contraceptive
combined transdermal patch
combined vaginal ring
drospirenone
deep vein thrombosis
emergency contraception
ethinylestradiol
follicle-stimulating hormone
Faculty of Sexual & Reproductive Healthcare
guideline development group
human chorionic gonadotrophin
healthcare practitioner
hormone-free interval
heavy menstrual bleedinghazard ratio
hormone replacement therapy
high-sensitivity urine pregnancy test
incidence rate ratio
intrauterine systemlong-acting reversible contraception/contraceptive
luteinising hormone
levonorgestrel
myocardial infarction
norethisterone
National Institute for Health and Care Excellenceoral contraception/contraceptive
polycystic ovary syndrome
premenstrual dysphoric disorderpremenstrual syndrome
progestogen-only pill
Royal College of Obstetricians and Gynaecologists
randomised controlled trial
relative risk
sexually transmitted infection
United Kingdom Medical Eligibility Criteria for Contraceptive Useulipristal acetate
unprotected sexual intercourse
venous thromboembolism
World Health Organization

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FSRH guideline: CHC

Grading of recommendations
Please refer to Appendix 1 for a full explanation of the classification of evidence level and gradingof recommendations.

A

At least one meta-analysis, systematic review or randomised controlled trial (RCT)
rated as 1++, and directly applicable to the target population;or
A systematic review of RCTs or a body of evidence consisting principally of studies
rated as 1+, directly applicable to the target population and demonstrating overall
consistency of results.

B

A body of evidence including studies rated as 2++ directly applicable to the target
population and demonstrating overall consistency of results;orExtrapolated evidence from studies rated as 1++ or 1+.

C

A body of evidence including studies rated as 2+ directly applicable tothe target population and demonstrating overall consistency of results;orExtrapolated evidence from studies rated as 2++.

D

Evidence level 3 or 4;
orExtrapolated evidence from studies rated as 2+.

✓

Good Practice Point based on the clinical experience of the guideline development group.

List of tables and boxes
Table 1

Standard and tailored regimens for use of combined hormonal contraception (CHC)

Table 2Starting combined hormonal contraception and requirement for additional contraceptive
precautions

Table 3aSwitching from hormonal contraceptive method to combined hormonal contraception

Table 3b

Switching from non-hormonal contraceptive method to combined hormonal contraception

Table 4

Percentage of women experiencing an unintended pregnancy within the first year of use withtypical use and perfect use

Table 5

European Medicines Agency estimated risk of developing venous thromboembolism (VTE) ina year according to type of combined hormonal contraceptive method used

Table 6

Definition of categories for the UK Medical Eligibility Criteria for Contraceptive Use (UKMEC)

Table 7

Recommendations for additional contraceptive precautions when switching from combined
hormonal contraception to another method

Box 1

Criteria for reasonably excluding pregnancy

Box 2

Suggested content of an initial combined hormonal contraception consultation (links tosubsequent sections)Box 3

Key messages for women considering use of tailored combined hormonal contraception regimens

Box 4

Women using combined hormonal contraception: key indications for medical review

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FSRH guideline: CHC

Contents
Abbreviations usediii

Grading of recommendations

iv

List of tables and boxes

iv

Contentsv

Executive summary of recommendationsx

1

Purpose and scope

1

2

Identification and assessment of the evidence

13

Introduction

2

4

Summary, including changes to existing guidance

2

5

What is combined hormonal contraception?

4

5.1

Hormonal content of combined hormonal contraception

4

5.1.1

Estrogens

4

5.1.2

Progestogens

4

6

5.2

What methods of CHC are available in the UK?

55.3

How does CHC work?

5

How is CHC used?

5

6.1

Standard CHC regimens

6

6.1.1

Combined oral contraception

6

6.1.2

Combined transdermal patch

6

6.1.3

Combined vaginal ring6

6.2

Tailored CHC regimens

6

6.2.1

Suggested tailored CHC regimens

7

6.2.2

Contraceptive effectiveness of tailored CHC regimens

7

6.2.3

Safety of tailored CHC regimens

8

6.2.4

Bleeding patterns with extended CHC regimens

9

6.2.5

Tailored CHC regimens and symptoms associated with the HFI

9

6.2.6

Return to fertility after use of extended CHC regimens

10

6.2.7

Acceptability of tailored CHC regimens

10

6.2.8

Offering tailored CHC regimens

11

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FSRH guideline: CHC
6.3

7

8

9

vi

When can CHC be started?

11

6.3.1

Starting CHC at the beginning of a natural menstrual cycle

12

6.3.2

Quick starting CHC

12

6.3.3

Summary of advice for starting CHC

13

6.3.4

Switching to CHC from other contraceptive methods

14

How effective is CHC?

16

7.1

Contraceptive effectiveness of CHC

16

7.2

What can affect contraceptive effectiveness of CHC?

18

7.2.1

Is contraceptive effectiveness of CHC affected by obesity/weight?

18

7.2.2

Is contraceptive effectiveness of CHC affected by bariatric surgery?

18

7.2.3

What drug interactions are important to consider in relation to CHC?

19

7.2.4

Severe diarrhoea or vomiting

21

Incorrect use of CHC

21

8.1

Combined oral contraception

21

8.2

Combined transdermal patch

22

8.3

Combined vaginal ring22

Non-contraceptive health benefits associated with CHC use

23

9.1

Heavy menstrual bleeding

23

9.2

Menstrual pain

23

9.3

Acne

24

9.4

Premenstrual symptoms

24

9.4.1

EE/DRSP COC for management of premenstrual symptoms

24

9.4.2

Other COC for management of premenstrual symptoms

24

9.4.3

Extended COC regimens for management of premenstrual symptoms

24

9.5

Vasomotor symptoms

25

9.6

Bone health

25

9.7

Endometriosis

25

9.8

Polycystic ovary syndrome

26

9.9

Effect of CHC use on cancer risk and mortality

27

9.9.1

Endometrial cancer

27

9.9.2

Ovarian cancer

28
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FSRH guideline: CHC
28

9.9.3

Colorectal cancer

9.9.4

Mortality

28

10 Health risks associated with CHC use

29

10.1 Venous thromboembolism (VTE) (including deep vein thrombosis and pulmonary embolism)29

10.1.1 Effect of progestogen type on VTE risk

29

10.1.2 Effect of dose of EE on VTE risk

30

10.1.3 Effect of estrogen type on VTE risk

30

10.1.4 Effect of route of administration on VTE risk

31

10.1.5 Women with inherited thrombophilias

31

10.2 Arterial thromboembolic disease32

10.2.1 CHC use and risk of myocardial infarction

33

10.2.2 CHC use and risk of ischaemic stroke

33

10.2.3 Estrogen dose and risk of ATE

33

10.2.4 Progestogen type and risk of ATE

34

10.2.5 Estrogen type and risk of ATE

34

10.2.6 Route of administration and risk of ATE

34

10.2.7 Additional risk factors for ATE

34

10.3 CHC use and risk of haemorrhagic stroke

35

10.4 Breast cancer

35

10.4.1 CHC use and risk of breast cancer

35

10.4.2 Family history of breast cancer

36

10.4.3 Genetic mutations relevant to breast cancer risk

36

10.5 Cervical cancer
11 Side effects associated with CHC use

37
37

11.1 CHC and headache

38

11.2 Unscheduled bleeding with CHC (breakthrough bleeding)38

11.2.1 Differences in bleeding pattern between routes of CHC administration

38

11.2.2 Differences in bleeding patterns between formulations of oral contraceptives

39

11.2.3 Differences in bleeding patterns between CHC regimens

40

11.3 Mood

40

11.4 Weight gain42

11.5 Effect on libido

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FSRH guideline: CHC
11.6 Return to fertility

42

12 What should be done in an initial CHC consultation?

43

12.1 Assessment of suitability of CHC for an individual woman

44

12.1.1 Assessment of medical eligibility for CHC

44

12.1.2 Assessment of factors that could affect contraceptive effectiveness46

12.1.3 Women for whom CHC is unsuitable47

12.2 Choosing a method of contraception

47

12.3 Choosing type and formulation of CHC

47

12.4 Choosing a regimen for CHC use

47

12.5 Other important supporting information48

12.6 Duration of CHC prescription

49

12.6.1 Combined oral contraception

49

12.6.2 Combined transdermal patch

50

12.6.3 Combined vaginal ring50

13 What follow-up is required for women continuing with use of CHC?
13.1 What follow-up arrangements are appropriate?
13.1.1 What should be done at CHC follow-up?
13.2 Online and remote provision of CHC
14 What specific advice is required for women using CHC?
14.1 CHC use during travel

50
50
51
52
52

14.1.1 VTE risk during travel52

14.1.2 Adherence to CHC when crossing time zones

52

14.2 CHC use at high altitude52

14.3 Surgery/periods of immobilisation

53

15 What recommendations are there regarding stopping CHC?
15.1 How long can women use CHC?

53
53

15.1.1 Use of CHC by women aged over 40 years

53

15.1.2 Duration of CHC use

54

15.2 Switching to another method of contraception

54

15.3 Planning pregnancy

54

15.3.1 Return of fertility
15.3.2 Preconception care
viii

50

54
54
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15.3.3 Unplanned pregnancy during CHC use

FSRH guideline: CHC
54

16 Use of CHC in the perimenopause

55

16.1 Use of CHC as an alternative to HRT

55

16.2 Transition to HRT

55

Recommendations for future research

55

Considerations for implementation of this guideline

55

Useful links

55

References

56

Appendices83

Appendix 1: FSRH Clinical Guideline Development Process

83

Appendix 2: Sections of UKMEC that contain conditions that are UKMEC 3 or 4 for use of
combined hormonal contraception

88

Questions for continuing professional development

91

Auditable outcomes

92

Comments and feedback on published guideline

93

Correction notice

94

Information box
Title

Combined Hormonal Contraception

Author/Publisher
Publication dateFaculty of Sexual & Reproductive Healthcare
January 2019 (Amended November 2020)

Superseded document
Review date
Available online

Combined Hormonal Contraception 2011
January 2024

https://www.fsrh.org/Public/Documents/fsrh-guideline-combinedhormonal-contraception.aspx

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FSRH guideline: CHC

Executive summary of recommendations
How is CHC used?
Key information✓

Tailored combined hormonal contraceptive (CHC) regimens can reduce thefrequency of withdrawal bleeds and can reduce withdrawal symptoms associatedwith the hormone-free interval (HFI); however, unscheduled bleeding is common.

Clinical recommendations✓

Women should be given information about both standard and tailored CHC
regimens to broaden contraceptive choice.

✓

Women should be advised that use of tailored CHC regimens is outside the
manufacturer’s licence but is supported by the Faculty of Sexual & Reproductive
Healthcare (FSRH).

✓

Women should have access to clear information (either written or digital) to support
tailored CHC use.

When can CHC be started?
Key information

D

CHC containing ethinylestradiol (EE) can be started by medically eligible women up
to and including Day 5 of a natural menstrual cycle without the need for additional
contraceptive protection.

D

CHC containing EE can be quick started by medically eligible women at any othertime (with advice to use additional contraceptive precaution for 7 days) if:► It is reasonably certain that the woman is not pregnant
OR► A high sensitivity urine pregnancy test is negative (even if there is a risk ofpregnancy from unprotected sexual intercourse [UPSI] in the last 21 days). A
follow up high sensitivity urine pregnancy test is required 21 days after thelast UPSI.

How effective is CHC?
Contraceptive effectiveness of CHC
Key information

C

Contraceptive effectiveness of all CHC is similar.

✓

If used perfectly, CHC is very effective for contraception. With typical use, CHC
is less effective for contraception than long-acting reversible contraception(LARC).

Clinical recommendation✓x

Women requesting CHC should be informed about the effectiveness (with both
typical and perfect use) of CHC and other contraceptive methods, including thesuperior effectiveness of LARC.
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FSRH guideline: CHC

Is contraceptive effectiveness of CHC affected by obesity/weight?
Key information

C

Most evidence suggests no association between weight/body mass index (BMI)
and effectiveness of combined oral contraceptives (COC).

D

Limited evidence suggests a possible reduction in patch effectiveness in women≥90 kg.

Is contraceptive effectiveness of CHC affected by bariatric surgery?
Clinical recommendation

D

Women who have had bariatric surgery should be advised that the effectiveness of
COC could be reduced.

Enzyme-inducing drugs
Clinical recommendations

D

Women using enzyme-inducing drugs should be informed that the contraceptive
effectiveness of CHC could be reduced during use of the enzyme-inducer and for
28 days after stopping.

D

Women using enzyme-inducing drugs should be offered a reliable contraceptive
method that is unaffected by enzyme-inducers.

Lamotrigine
Clinical recommendation

D

Women taking lamotrigine should be advised that CHC may interact withlamotrigine; this could result in reduced seizure control or lamotrigine toxicity.
The risks of using CHC could outweigh the benefits.

Antibiotics (non enzyme-inducing)
Key information

D

Additional contraceptive precautions are not required when antibiotics that do not
induce enzymes are used in conjunction with CHCs.

Progestogen receptor modulators
Clinical recommendation

D

Women should be advised to wait 5 days after taking ulipristal acetate for emergency
contraception (UPA-EC) before starting CHC. Women should be made aware thatthey must use condoms reliably or abstain from sex during the 5 days waiting andthen until their contraceptive method is effective.

Severe diarrhoea or vomiting
Clinical recommendation✓

Women using COC should be advised that contraceptive effectiveness could be
reduced by vomiting or severe diarrhoea.

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Incorrect use of CHC
See FSRH Guidance on Incorrect Use of Combined Hormonal Contraception.
Non-contraceptive health benefits associated with CHC use
Key information✓

Use of CHC for contraception may also be associated with non-contraceptive
health benefits

B

Use of CHC can reduce heavy menstrual bleeding (HMB) and menstrual pain andimprove acne.

C

Use of CHC may be beneficial for women with premenstrual syndrome (PMS)
symptoms.

A

Use of CHC (particularly continuous CHC regimens) can reduce risk of recurrenceof endometriosis after surgical management.

B

CHC can be used for management of acne, hirsutism and menstrual irregularities
associated with polycystic ovary syndrome (PCOS).

CCHC use is associated with a significant reduction in risk of endometrial and ovariancancer that increases with duration of CHC use and persists for many years after
stopping CHC.

C

Use of CHC is associated with a reduced risk of colorectal cancer.

Health risks associated with CHC use
Clinical recommendation✓

Women should be informed about the health risks associated with use of CHC.

Venous thromboembolism (VTE) (including deep vein thrombosis and pulmonary embolism)
Key information

C

Current use of CHC is associated with increased risk of VTE; some CHC formulations
are associated with a greater risk of VTE than others, dependent on progestogen
type and estrogen dose.

Clinical recommendation

C

Women should be advised that use of CHC is associated with an increased risk of
VTE, but the absolute risk of VTE for an individual CHC user remains very small.

Arterial thromboembolic disease
Key information

C

xii

Current use of CHC is associated with a very small increased risk of myocardial
infarction (MI) and ischaemic stroke that appears to be greater with higher doses of
estrogen in COC.

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FSRH guideline: CHC

Clinical recommendation

C

Women should be informed that current use of CHC is associated with an increased
risk of MI and ischaemic stroke but that that these events are still extremely
uncommon in CHC users.

✓

Use of CHC by women with significant additional risk factors for arterial disease
should be strongly cautioned or avoided.

Breast cancer
Clinical recommendation

C

Women should be advised that current use of CHC is associated with a small
increased risk of breast cancer which reduces with time after stopping CHC.

Cervical cancer
Clinical recommendation

C

Women should be advised that current use of CHC for more than 5 years is
associated with a small increased risk of cervical cancer; risk reduces over timeafter stopping CHC and is no longer increased by about 10 years after stopping.

What should be done in an initial CHC consultation?
Assessment of suitability of CHC for an individual woman
Key informationC

Use of suitable self-completed checklists for medical eligibility appears to beaccurate and acceptable to women.

Clinical recommendation✓

Assessment of medical eligibility for CHC should include medical conditions,
lifestyle factors and family medical history✓

A drug history should identify:► any prescribed or non-prescribed drug that could affect the effectiveness of thecontraceptive► any prescribed or non-prescribed drug that could itself be affected by thecontraceptiveC

A recent, accurate blood pressure recording should be documented for all womenprior to first CHC prescription.

D
D

BMI should be documented for all women prior to CHC prescription.

D

Pelvic examination is not required prior to initiation of CHC.
Breast examination, cervical screening, testing for thrombophilia, hyperlipidaemia
or diabetes mellitus and liver function tests are not routinely required prior toinitiation of CHC.

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FSRH guideline: CHC✓

Women for whom CHC is unsuitable should be offered alternative effective
contraception.

Choosing type and formulation of CHC
Key information✓

COC containing ≤30 μg EE in combination with levonorgestrel or norethisterone isa reasonable first-line choice of CHC to minimise cardiovascular risk.

Other important supporting information
Clinical recommendation✓

Women should be provided with written information or a link to a trusted online
resource to support safe, effective CHC use.

Duration of CHC prescription
Clinical recommendation
HCP can prescribe up to 12 months’ supply of CHC for women who are initiating or
continuing CHC.
What follow-up is required for women continuing with use of CHC?

C

What follow-up arrangements are appropriate?
Clinical recommendation✓

Women should be advised that routine annual review of their contraception isrecommended during CHC use.

What should be done at CHC follow-up?
Clinical recommendation✓

Medical eligibility, drug history, method adherence and method satisfaction should
be reassessed at follow up. BMI and blood pressure should be recorded.

What specific advice is required for women using CHC?
CHC use during travel
Clinical recommendation

C

Women using CHC should be advised about reducing periods of immobility during
travel.

CHC use at high altitude
Clinical recommendation

D

xiv

Women trekking to high altitudes (above 4500 m or 14 500 feet) for periods ofmore than 1 week may be advised to consider switching to a safer alternative
contraceptive method.

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FSRH guideline: CHC

Surgery/periods of immobilisation
Clinical recommendation

D

Women should be advised to stop CHC and to switch to an alternative contraceptive
method at least 4 weeks prior to planned major surgery or expected period of limited
mobility.

What recommendations are there regarding stopping CHC?
How long can women use CHC?
Clinical recommendation

D

CHC can be used by medically eligible women for contraception until age 50 years.

Use of CHC in the perimenopause
Use of CHC as an alternative to hormone replacement therapy (HRT)
Clinical recommendation

D

CHC can be considered for use by medically eligible women until age 50 as analternative to HRT for relief of menopausal symptoms and prevention of loss ofbone mineral density as well as for contraception.

FSRH Guideline (January 2019, amended November 2020)
Combined Hormonal Contraception(Revision due by January 2024)
1. Purpose and scopeThis document updates previous Faculty of Sexual & Reproductive Healthcare (FSRH) guidance andaims to summarise the available evidence and expert opinion on combined hormonal contraception(CHC). The guideline is intended for use by healthcare practitioners (HCPs) providing CHC.

2. Identification and assessment of the evidenceThis guideline was developed in accordance with standard methodology for developing FSRH
clinical guidelines. The recommendations made within this document are based on the best available
evidence and the consensus opinion of experts and the guideline development group (GDG). The
methodology used in developing this guideline and a list of GDG members and other contributors
can be found in Appendix 1.
The recommendations included should be used to guide clinical practice but are not intended toserve alone as a standard of medical care or to replace clinical judgement in the management of
individual cases.

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FSRH guideline: CHC

3. Introduction
CHC has been used by women worldwide for almost 60 years, with significant changes in dosage
and preparation over time. Millions of UK women choose to use CHC. The Natsal 3 survey1 carriedout in 2010–2012 reported that more than a third of UK women aged 16–44 years had used oral
contraception (OC) in the last year (no distinction was made between combined oral contraception(COC) and the progestogen-only pill (POP)), but data from the Office for National Statistics (2008/09)2
indicate that the majority of women using OC choose COC. 2
HCPs should support women to make informed decisions about choosing and using CHC,
ensuring that they are informed about contraceptive effectiveness (and how this compares to othercontraceptive methods) as well as potential risks and benefits.
Extrapolation of COC data to inform recommendation on all CHC methods
Unless stated otherwise, the recommendations for COC in this guideline refer to low-dose COC
containing ≤35 μg ethinylestradiol (EE) combined with a progestogen. Recommendations are thesame for all COC formulations, irrespective of their progestogen content. Data relating to COC
containing estradiol are very limited; recommendations for these preparations are currently as for
EE-containing COC.
Limited information is available on the short- and long-term safety of the combined transdermal
patch (CTP) and combined vaginal ring (CVR); most of the available studies were sponsored by the
manufacturers. After reviewing the available evidence, the GDG considers that recommendations for
COC can be extrapolated to include CTP and CVR, unless stated otherwise.

4. Summary, including changes to existing guidance
CHC contains an estrogen and a progestogen delivered as a pill (COC), transdermal patch (CTP) or
vaginal ring (CVR).
Contraceptive effectiveness: CHC is highly user-dependent. If used perfectly, the risk of CHC
contraceptive failure is low (<1%), but with typical use it is estimated that 9% of women have
unplanned pregnancies in the first year of CHC use. Effectiveness could also be affected by druginteractions (all CHC methods) and malabsorption (COC only); the CTP could be less effective in
women weighing >90 kg. See Section 7.
Health risks: The increased risk of serious health events, including venous and arterial
thromboembolism, breast cancer and cervical cancer associated with current or recent use of CHC
is small, but is greater than that with progestogen-only or non-hormonal contraception.
Levonorgestrel (LNG), norethisterone (NET) and norgestimate COC are associated with a lower riskof venous thromboembolic events than COC containing newer progestogens, the CTP and the CVR.
COC containing higher EE doses may be associated with greater risk of arterial thrombotic events
than lower EE doses. See Section 10.
Health benefits: Ever-use of CHC is associated with a reduced risk of endometrial, ovarian andcolorectal cancer; other non-contraceptive benefits of CHC use include predictable bleeding
patterns, reduction in menstrual bleeding and pain, and management of symptoms of polycystic
ovary syndrome (PCOS), endometriosis and premenstrual syndrome. See Section 9.

2

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FSRH guideline: CHC

Side effects: CHC use – and the hormone-free interval (HFI) – can be associated with side effects
including mood change, headache and unscheduled bleeding. There is no one CHC formulation thatis associated overall with fewest unwanted nuisance effects. See Section 11.
CHC regimens: The traditional 21/7 CHC regimen with a monthly withdrawal bleed confers nohealth benefit over other patterns of CHC use. In addition, symptoms associated with the HFI canbe problematic and ovarian activity during a 7-day HFI could risk escape ovulation (particularly withlower doses of EE and if use is not perfect). This guideline highlights the fact that ‘tailored’ CHC
regimens in which there are fewer (or no) HFI and/or shortened HFI can be safely used to avoid
withdrawal bleeds and associated symptoms and theoretically reduce the risk of contraceptive failure.
Suggested tailored regimens (using a monophasic EE CHC) are described. Women should be told
about tailored regimens and given their choice of regimen based on their preference. See Section 6.
Medical eligibility: Contraindications to use of CHC are unchanged in this guideline, in line with United
Kingdom Medical Eligibility Criteria (UKMEC) 2016. Women aged over 50 years should generally
use safer alternative contraception. Information and checklists are provided to support clinicians withassessment of medical eligibility for CHC. The guideline notes that appropriate self-assessment medical
questionnaires can be safe and useful tools that may also facilitate remote prescribing; advice is given
about obtaining blood pressure and body mass index (BMI) measurements. See Section 12.1.1.
Concomitant use of other drugs: Hepatic enzyme-inducing drugs could reduce the contraceptive
effectiveness of all CHC methods. Contraceptive hormones can affect serum levels of drugs such as lamotrigine
with potential significant clinical effects. Women using teratogenic medications should be encouraged to use
the most effective long-acting reversible contraception (LARC) methods. See Section 7.2.3.
Choice of contraceptive method, CHC formulation and CHC regimen: A woman requesting CHC
who is medically eligible should be given information about the contraceptive effectiveness of CHC andalternatives including LARC. If CHC is the preferred option, a COC containing ≤30 g EE in combination
with LNG or NET is a reasonable first-line option to minimise venous thromboembolism (VTErisk; women
may choose other preparations or routes of administration depending on their past experience of side
effects and personal preference. Non-oral CHC may be considered if there are concerns about absorptionof COC. Women should be given the option of standard or tailored CHC regimens. See Section 12.
Starting CHC and supporting information: Charts and information boxes are provided to guidestarting CHC (see Section 6.3) and to support clinicians with informing women as to how to take
CHC, what to do if they make a mistake (see Section 8) and symptoms/new medical diagnoses thatshould prompt them to seek medical advice (see Box 4. Specific advice is given regarding CHC use
during travel, at high altitude, and during times of prolonged immobilisation (see Section 14).
Provision of CHC: Up to a year’s supply of CHC may be prescribed at the first consultation. See
Section 12.6.
Follow-up: Annual follow-up with review of medical eligibility, drug interactions, compliance andconsideration of alternative contraception including LARC is recommended as routine. See Section 13.
Stopping CHC: CHC use is not associated with a delay in return to fertility after stopping (seeSection 11.6. Guidance is given (see Table 3a and Table 3b) to support switching from CHC toother contraceptive methods. There is no arbitrary maximum period of CHC use. Repeated stoppingand starting of CHC should be discouraged because of thrombotic risk (see Section 10.1). Medically

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FSRH guideline: CHC

eligible women who are aware of effectiveness and associated health risks may choose to continue
CHC for contraception until age 50 years (see Section 15). CHC may be of benefit for menopausal
symptoms and maintenance of bone mineral density (BMD) in perimenopausal women aged under
50 years who also require contraception.

5. What is combined hormonal contraception?
5.1 Hormonal content of combined hormonal contraception
CHC contains an estrogen paired with a progestogen in different formulations.
5.1.1 Estrogens
In the UK, the majority of COC as well as the CTP and CVR, contain between 20 μg and 35 μg of thesynthetic estrogen, EE. Current ‘low-dose’ COC was developed to reduce the health risks associatedwith the high estrogen content of COC in the 1960s and 1970s.3 A COC product containing the synthetic
estrogen, mestranol (metabolised to EE) is also available (50 μg mestranol roughly equates to 35 μg EE).4
COC has been introduced that contains 17β-estradiol, structurally identical to that which occurs
naturally in humans. Theoretically, estradiol COC could have improved safety profiles compared toformulations containing EE or mestranol due to reduced thrombotic and metabolic effects.5 This has
not yet been established: although limited evidence suggests that estradiol COC is safe to use andhighly effective in preventing unintended pregnancy,6 further research will be required to assess thesafety profile of estradiol COC relative to that of EE COC.
5.1.2 Progestogens
Progestogens are synthetic steroids designed to have some of the properties of progesterone. The
synthetic progestogen component of CHC allows convenient dosing intervals, potent suppressionof ovulation, and prevents over-proliferation of the endometrium in response to estrogen. Newer
progestogens were developed to have fewer androgenic and glucocorticoid effects; some areanti-androgenic and have potentially favourable anti-mineralocorticoid effects.7
However, different progestogens may modify the effect of EE on hepatic clotting factors differently;
CHC containing some newer progestogens in combination with EE appear to be associated withgreater risk of VTE than COC containing other progestogens. See Section 10.1.1.
The progestogens that are components of CHC are sometimes grouped by ‘generation’, according
to the time they were first marketed as constituents of COCs.7,8 (note that classification varies).
►►►►

First:
Second:Third:
Newer/other:

norethisterone (NET)levonorgestrel (LNG)
desogestrel, gestodene, norgestimate*drospirenone (DRSP), dienogest, nomegestrol acetate(*sometimes classified as second generation: LNG is one of its active metabolites).
Norelgestromin is a metabolite of norgestimate; etonogestrel is the active metabolite of desogestrel.
Co-cyprindiol (containing 35 µg EE with cyproterone acetate, an anti -androgen) is indicated for
management of moderate to severe acne and hirsutism. Women using co-cyprindiol for these
indications do not require additional contraception.9
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5.2 What methods of CHC are available in the UK?
There are currently three methods of CHC available in the UK:►►►

Combined oral contraceptive pill (COC)
Combined transdermal patch (CTP) that releases an average of 33.9 μg EE and 203 μg
norelgestromin per 24 hours.10
Combined vaginal ring (CVR) that releases EE and etonogestrel at daily rates of 15 μg and120 μg, respectively.11

Monophasic verses multiphasic COC
The majority of COC products in the UK are monophasic; that is, all pills in the packet contain thesame dose of estrogen and progestogen. Multiphasic (variable dose) COC is also available in which
the dose of either or both steroid hormones varies during the pill cycle.
Cochrane Reviews of randomised controlled trials (RCTs) comparing monophasic with biphasic,
triphasic and quadriphasic COC regimens identified extremely limited evidence. 12–15 The COC
regimens studied differed not only because they were differently phasic, but also contained different
progestogens. For example, the only quadriphasic preparation studied contained estradiol valerate
which was compared with a monophasic preparation containing EE. Evidence is inadequate toestablish whether multiphasic COC differs significantly from monophasic COC in terms of bleeding
patterns, side effects, discontinuation rates or effectiveness in preventing pregnancy. As the existing
evidence suggests no particular advantage associated with multiphasic preparations, the GDG
recommends that monophasic COC should be used first-line.
5.3 How does CHC work?
The primary mechanism of action of CHC is prevention of ovulation. CHC acts on the hypothalamopituitary-ovarian axis to suppress luteinising hormone (LH) and follicle-stimulating hormone (FSH)
and thus inhibit ovulation.16–19 Changes to cervical mucus, endometrium and tubal motility that result
from progestogen exposure may also contribute to the contraceptive effect.

6. How is CHC used?
Key information✓

Tailored CHC regimens can reduce the frequency of withdrawal bleeds and can
reduce withdrawal symptoms associated with the hormone-free interval (HFI);
however, unscheduled bleeding is common.

Clinical recommendations✓

Women should be given information about both standard and tailored CHC regimens
to broaden contraceptive choice.

✓

Women should be advised that use of tailored CHC regimens is outside the
manufacturer’s licence but is supported by FSRH.

✓

Women should have access to clear information (either written or digital) to support
tailored CHC use.

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FSRH guideline: CHC

Traditional (standard) 21/7 CHC cycles were designed to induce a bleed each month, mimicking
naturally occurring menstrual cycles. There is, however, no health benefit from a monthly withdrawal
bleed, and the 7-day HFI has the following drawbacks:►►►

Withdrawal bleeding may be heavy, painful or simply unwanted.
The HFI may be associated with symptoms such as headache and mood change.
Ovarian suppression is reduced,20–26 and follicular development occurs during the HFI, particularly
with COC containing lower EE doses.20–23 Errors in pill-taking (or patch or ring use) around the
HFI could result in extension of the HFI, risk of ovulation, and thus potential risk of pregnancy.

Tailored (non-standard) CHC regimens reduce the frequency of HFI (extended regimens), abolishthe HFI (continuous regimens) and/or shorten the HFI. Using tailored regimens, women can reduceor avoid HFI-associated symptoms and could potentially reduce the risk of escape ovulation andresulting contraceptive failure. Such regimens are as safe and as effective for contraception as
standard 21/7 regimens.27,28
The GDG recommends that the tailored CHC regimens suggested in Section 6.2.1 can be offered
as an alternative to 21/7 CHC regimens to widen contraceptive choice. Women should have accessto clear information (either written or digital) to support tailored CHC use.
6.1 Standard CHC regimens
6.1.1 Combined oral contraception
The majority of COC in the UK is designed to be taken as 28-day cycles, with 21 consecutive daily
active pills followed by a 7-day HFI prior to starting the next packet of pills. The first seven pills inhibit
ovulation29 and the remaining 14 pills maintain anovulation. Traditionally women have then either
had seven pill-free days or taken seven placebo tablets; during this HFI, most women will have awithdrawal bleed due to endometrial shedding. It should be made clear to women that this bleed
does not represent physiological menstruation and that it is has no health benefit.
6.1.2 Combined transdermal patch
One patch is applied to the skin and worn for 7 days to suppress ovulation. Thereafter the patch is
replaced on a weekly basis for two further weeks. The fourth week is patch-free to allow a withdrawal
bleed. A new patch is then applied after seven patch-free days.
6.1.3 Combined vaginal ring
One ring is inserted into the vagina and left in place continuously for 21 days. After a ring-free intervalof 7 days to induce a withdrawal bleed, a new ring is inserted.
6.2 Tailored CHC regimens
Tailored CHC regimens include:►►►

Continuous use of CHC (no HFI)Extended use of CHC (less frequent HFI); timing of HFI can be fixed or flexible
CHC regimens in which the HFI is shortened (the shortened HFI may be taken after each 21 daysof CHC use or incorporated into an extended regimen).

In continuous or extended CHC regimens, CHC is taken for more than 21 consecutive days without
a HFI. Such regimens have the potential advantage of eliminating or reducing the frequency

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FSRH guideline: CHC

of withdrawal bleeding and associated symptoms; bleeding pattern is, however, unpredictable.
Less frequent HFI could also reduce the risk of escape ovulation 20 and (potentially) contraceptive
failure.
A shortened HFI, offering more continuous ovarian suppression, could also reduce the risk of escapeovulation,20 particularly if CHC use is imperfect around the HFI. A shortened HFI can be taken after
every 21 days of active CHC or incorporated into an extended regimen.
6.2.1 Suggested tailored CHC regimens
A variety of regimens have been studied; however, data are currently too limited to recommend
one approach over another. In some countries (but not the UK) COC are available that are
intended to be taken as an 84/7 regimen, with a 3-monthly HFI. In the UK, some monophasic
24/4 COC regimens are marketed30,31 and one quadriphasic COC with a 2-day HFI is available.32
The FSRH supports off-label use of tailored CHC regimens such as those detailed in Table 1
using monophasic CHC that are licensed to be taken as a 21/7 regimen. If the preparation
includes placebo pills, these should be omitted. Multiphasic COC should not be used in tailored
regimens.
Table 1: Standard and tailored regimens for use of combined hormonal contraception (CHC)
Type of regimen
Standard use

Period of CHC use
21 days (21 active pills or 1 ring, or 3 patches)

HFI
7 daysShortenedhormone-freeinterval (HFI)

21 days (21 active pills or 1 ring, or 3 patches)

4 daysExtended use (tricycling)

9 weeks (3 x 21 active pills or 3 rings, or 9 patches used 4 or 7 days
consecutively)
Continuous use (≥21 days) of active pills, patches or rings
4 daysuntil breakthrough bleeding occurs for 3–4 days

Tailored use

Flexible extended use
Continuous use

Continuous use of active pills, patches or ringsNone

6.2.2 Contraceptive effectiveness of tailored CHC regimens
How does contraceptive effectiveness of tailored regimens compare with standard
regimens?
It has been suggested that reducing the frequency of the HFI, abolishing the HFI and/or shortening
the HFI could reduce the risk of escape ovulation and resulting contraceptive failure.
The findings of studies that consider the contraceptive effectiveness of tailored CHC regimens
compared to one another and to standard 21/7 regimens are difficult to bring together because
they consider different CHC formulations (different doses of estrogen, different progestogens) anddifferent regimens. In addition to very limited direct data from studies with pregnancy as an outcome,indirect evidence is available from studies that consider ovarian activity during HFI of various lengths
as a marker of potential risk of pregnancy.
On the basis of the available evidence (summarised below), the GDG considers that extended orcontinuous CHC regimens and shortened HFI could theoretically reduce risk of escape ovulationcompared with standard CHC regimens, but that there is not conclusive evidence of greater
contraceptive effectiveness.

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Studies considering ovarian activity in the HFI as an indication of risk of pregnancy
A standard 7-day HFI is associated (in most studies) with more hypothalamic-pituitary-ovarian
axis activity than a shortened, 3- or 4-day HFI.24,25,33–36 Ovarian activity has been observed to besignificantly lower with continuous COC than with standard 21/7 regimens.37,38 It has therefore beensuggested that a regimen including a HFI shorter than 7 days could reduce the risk of pregnancy
resulting from escape ovulation.
Imperfect use of CHC in the days around the HFI could in effect extend the HFI. A systematic
review39 identified 10 biomedical studies that reported on risk of ovulation with a deliberately
extended HFI. Findings varied: five studies observed no ovulations with extended HFI up to
14 days; in the other five studies, presumed ovulations were documented with HFI between 8
and 11 days long. All studies involved small numbers of women and used different definitions andindicators of ovulation. A shorter HFI could theoretically reduce the risk of ovulation if CHC use
around the HFI is imperfect.
One small RCT found that endogenous estradiol levels increased more quickly during the HFI after
extended (84/7) COC use than in a 21/7 regimen.40 The authors postulated, but did not demonstrate,that escape ovulation could occur earlier with extended than with standard COC regimens.
There is limited evidence that ovarian activity in the HFI could be more pronounced in obese
women. In one study41 hormone profiles at the end of a 7-day HFI in 10 women with normal BMI and
10 women with obesity noted estradiol levels consistent with dominant follicles and progesterone
levels consistent with ovulation in more women with obesity than women with normal BMI. A further
study42 of women with obesity who were initially taking 20 µg EE COC in a 21/7 regimen and werethen randomised to either a continuous regimen of 20 µg EE COC or to 30 µg EE COC as a 21/7
regimen noted that both options decreased evidence of a follicle-like structure compared with 20 µg
EE taken in a 21/7 regimen.
Studies with pregnancy as an outcome
A systematic review39 identified no direct evidence for risk of pregnancy associated with a HFIextended beyond 7 days.
The RCTs identified by a 2014 Cochrane Review27 were not powered to detect significant differencesin pregnancy risk between continuous/extended and cyclical CHC regimens; only one reported asignificantly lower risk of pregnancy with continuous compared to cyclical (vaginal) administration of
COC (odds ratio (OR) 0.14, 95% confidence interval (95% CI) 0.02–0.97).43 One RCT published after
the Cochrane Review (and designed to investigate continuation rather than effectiveness) reported
similar pregnancy rates among 358 women randomised to either cyclical or continuous use of the same
COC.44
Some observational studies suggest that risk of pregnancy associated with extended CHC
regimens45 or CHC regimens with shortened HFI 46 could be lower than that with traditional 21/7
regimens. A study47 examining pregnancy rates during an extended 91-day CHC regimen with
20 µg EE noted no reduction in contraceptive efficacy in women with obesity compared to women
without obesity.
6.2.3 Safety of tailored CHC regimens
Available information regarding safety of extended compared to standard CHC regimens isreassuring. RCTs comparing extended and standard CHC regimens record very few serious adverse
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events associated with either type of regimen.27 Observational studies report similar (small) numbersof serious adverse events for extended regimens and for regimens with shortened HFI compared to
21/7 regimens.48,49
Direct data comparing risk of cardiovascular events and cancer between extended and standard
CHC regimens are lacking. However, indirect evidence regarding cardiovascular risk is reassuring.
In a Phase 3 trial of 20 µg EE/DRSP COC, 1067 women were randomised to standard cyclical,
flexible extended or fixed extended pill-taking regimens for 1 year. A total of 755 women then enteredan extension phase, taking the flexible extended regimen. Metabolic and haemostatic parameters,
serum hormone levels and blood pressure were similar in all groups. Numbers of serious adverse
events were very low in all groups.50 A smaller trial which randomised 78 women to use extended
or standard cyclical regimens of 30 µg EE/DRSP COC found no statistically significant differences
in carbohydrate or lipid profiles between the two groups over 6 months of use.51 In a third trial,
174 women were randomised to cyclical or continuous use of 20 µg EE/LNG COC (the dose of LNG
was different in the two groups). The authors concluded that after 13 months of use, carbohydrate
metabolism, lipid profile and haemostatic variables were broadly similar between the groups, but thatfurther studies would be required to assess long-term continuous CHC.52 Haemostatic parameters
were reported to be similar for 187 women randomised to extended or cyclical use of 30 µg EE/LNG
COC for 6 months.53
Several studies have assessed the endometrium during continuous or extended CHC; endometrial
thickening and histological abnormalities were not observed. 27,50,54,55
6.2.4 Bleeding patterns with extended CHC regimens
A Cochrane Review of RCTs27 reported that in most studies bleeding patterns with extended CHC
regimens were equivalent or improved compared to standard regimens. 37,43,51,56–64 A systematic
review28 that included both RCTs and observational studies concluded that overall, the total numberof days of bleeding was lower with continuous or extended regimens than with cyclical use of
CHC. Although there was an increase in breakthrough bleeding during the first months of use ofcontinuous or extended regimens, its frequency and intensity subsequently decreased over time.
Limited evidence suggests that bleeding patterns with continuous or extended use of the CTP and
CVR show a similar reduction in bleeding/spotting days over time to that seen with extended use of
COC.59,62,65–67
One study68 compared bleeding patterns in 139 existing cyclic COC users who were randomised
to continuous use for 180 days of COC containing 30 µg EE/100 µg LNG, 20 µg EE/100 µg LNG,
30 µg EE/1000 µg NET or 20 µg EE/1000 µg NET; it should be noted that only the first of these is a
COC preparation available in the UK. The study suggested more favourable bleeding patterns (moreamenorrhoea and fewer spotting days) with continuous use of NET COC than with continuous use
of LNG COC. The authors noted that the study findings did not support use of higher EE doses toprevent breakthrough bleeding during continuous COC use. It is not known how bleeding patterns
with continuous use of other COC would compare.
6.2.5 Tailored CHC regimens and symptoms associated with the HFISymptoms such as headache, pelvic pain, bloating and breast tenderness are more frequent during
the HFI than during the time that CHC hormones are being taken.69,70 Women may choose extended
CHC regimens to avoid or reduce the frequency of symptoms associated with the HFI.

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A Cochrane Review27 of RCTs identified studies that reported improvement in menstrual-relatedheadache, bloating, tiredness and menstrual pain with extended COC regimens.
Observational studies similarly suggest benefit; a cohort study71 of 111 women who reported cyclicalsymptoms with two cycles of use of a 21/7 COC regimen found that mood, headache and pelvic
pain scores improved significantly after the women switched to an extended COC regimen andwere followed up for a year. Some 80% of the women continued the extended regimen for the fullyear, and 6 months after that most women reported that they had continued the extended regimen
on their own. A prospective cohort study72 of 109 women given 30 µg EE/DRSP COC for two
21/7 cycles, followed by two 84/7 cycles (two-thirds completed all cycles) reported a significantly
reduced incidence of heavy menstrual bleeding (HMB), intermenstrual bleeding, dysmenorrhoea,
abdominal bloating, depressed mood and irritability at the end of the second 84/7 cycle compared
to at enrolment.
6.2.6 Return to fertility after use of extended CHC regimens
One study73 found that of 187 women aged 18–49 years who had used continuous 20 µg EE/
LNG COC for at least 6 months, 98.9% returned to spontaneous menstruation or became
pregnant within 90 days. In another study, amongst 47 women who had used 20 µg EE/LNG
COC continuously for 84 days, ovulation was observed within 37 days of stopping treatment inall but one case (98%).74
6.2.7 Acceptability of tailored CHC regimens
Evidence indicates that continuous or extended CHC regimens offer an acceptable alternative tostandard CHC regimens for many women.
A UK trial56 randomised 503 women to use 30 µg EE/LNG COC either as a 21/7 regimen or asa regimen in which pills were taken consecutively until a 3-day bleed triggered a 3-day break inpill-taking. Of the 252 women using the tailored regimen, 179 women were followed up at 12 months;
54% were continuing the tailored regimen. This compared to 67% of women followed up in the
21/7 regimen arm of the study. Of note, there was no significant difference between standard andtailored regimens in terms of the proportion of women who continued taking any COC regimen at
12 months. The authors concluded that “tailored use can provide a suitable alternative to standard
COC use for selected women” and that “offering the tailored regimen is unlikely to increase the riskof discontinuation of the COC”. Qualitative research carried out as part of this trial showed that some
women using tailored COC regimens much preferred the reduced bleeding while others disliked theunpredictability of bleeding.56
A recent trial in Australia65 randomised 172 women to continuous use for a year of either
a CVR or 20 µg EE/LNG COC. Women were instructed to take a 4-day break if they bled
for four consecutive days. The study reported high satisfaction rates with continuous use ofboth methods; women liked the ease of use and infrequent bleeding, and for some women
the absence of dysmenorrhoea, headaches and premenstrual symptoms were particularadvantages. However, many women who were otherwise satisfied with the regimen disliked theunpredictability of bleeding.
A Cochrane Review27 identified six other RCTs that considered participant satisfaction with extended
regimens; satisfaction was high and similar for both traditional and extended regimens.

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A retrospective review75 of 318 women with unwanted hormone withdrawal symptoms on COC, whowere counselled about using extended COC regimens, reported that of the 292 women followed up,
267 women chose to start an extended regimen and 172 continued to use the extended regimen
at the time of their last follow-up. Various extended durations of pill-taking and shortened HFI wereused.
As far back as 1977, a UK cohort study76 of 202 women started on a tricycling COC regimen reported
that 82% of participants welcomed the reduction in bleed frequency. A total of 107 women completed
12 months of the tricycling regimen; of these 91% chose to continue the regimen after the trial had
finished. Surveys of women in Holland,77 Germany,78 the USA79,80 and Italy81 found that more thanhalf of the women of reproductive age would prefer to bleed less than once a month. In an Australiansurvey 54% of women preferred a monthly bleed.82
A Cochrane Review27 identified three RCTs in which study discontinuation rates were higher for
extended or continuous regimens than for traditional 21/7 cycles; 10 RCTs reported no significant
difference in discontinuation between regimens.
6.2.8 Offering tailored CHC regimens
In a UK study 112 women requesting COC (most already COC users) were given information about
tailored COC regimens by a HCP using a structured script and patient advice sheet. The information was
welcomed and understood by women and HCPs did not find the information-giving too time consuming.83
6.3 When can CHC be started?
Key information

D

CHC containing EE can be started by medically eligible women up to and including
Day 5 of a natural menstrual cycle without the need for additional contraceptive
protection.

D

CHC containing EE can be quick started by medically eligible women at any othertime (with advice to use additional contraceptive precaution for 7 days) if:► It is reasonably certain that the woman is not pregnant
OR► A high sensitivity urine pregnancy test is negative (even if there is a risk ofpregnancy from UPSI in the last 21 days). A follow up high sensitivity urine
pregnancy test is required 21 days after the last UPSI.

Established FSRH guidance is that CHC containing EE can be started up to
and including Day 5 of a natural menstrual cycle without the need for additional
contraceptive precaution. After Day 5, CHC can be ‘quick started’ with advice to
use additional contraceptive precautions (condoms or abstinence) during the first
7 days of CHC use (after seven consecutive days of CHC use, the evidence suggeststhat ovulation is inhibited).29 Follow-up pregnancy testing is required 21 days after
the last UPSI. This advice is in line with current recommendations in the USA andfrom the World Health Organization (WHO).84,85 See FSRH Guideline Quick Starting
Contraception.86

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FSRH guideline: CHC

6.3.1 Starting CHC at the beginning of a natural menstrual cycle
Five studies are identified by a recent systematic review 29 that consider the risk ofovulation (but not of pregnancy) if CHC is started at a time other than Day 1 of themenstrual cycle. Two small studies87,88 (n=14 and n=22) compared a group of womenstarting COC on Day 1 with a group starting on Day 5. No ovulations were observed, but
ovarian suppression was greater if COC was started on Day 1. In two larger studies89,90
comparing commencement of COC on Day 1 and Day 7, ovarian activity was greaterin the Day 7 group; risk of ovulation was significantly greater in the Day 7 group witha 20 µg EE, but not a 30 µg EE COC. However, markers used for occurrence ofovulation are not consistent across studies and frequency of ovulation may have been
overestimated. A study91 of 40 women randomised to start COC on Day 1 or CVR on
Day 5 observed no ovulations, but there was less ovarian suppression in the group
who started CVR on Day 5.

Evidencelevel 2-

In a study considering the effects of oral contraceptives administered at defined
stages of ovarian follicular development, no ovulations were observed when COC
was commenced at a follicle diameter of 10 mm (mean cycle Day 7.6). 92 However
5/14 women ovulated when COC was initiated at 14 ± 1 mm (mean Day 11.7 ± 0.7;
range Day 5–20) and 14/15 ovulated when COC was initiated at 18 ± 1 mm (mean Day
13.6 ± 0.8; range Day 7–20).

Evidencelevel 2-

No studies are identified that consider ovarian activity when starting the CTP on different cycle days
therefore advice is extrapolated from evidence for COC and CVR. Estradiol-containing COC should
be started on Day 1 of a natural menstrual cycle. If started at any other time, additional contraceptive
precautions are advised as per the manufacturer’s recommendations.
Women with short menstrual cycles
Fewer than 5% of women aged 15–44 years and fewer than 2% of women aged 20–
39 years have menstrual cycles shorter than 20 days. 93 Even smaller numbers (<1%)
of women aged 14–42 years have cycle lengths shorter than 15 days.94 However, if
there is concern about earlier ovulation associated with very short or variable cycles,
women can be given the option to use additional contraceptive precautions whenstarting CHC after Day 1.

Evidencelevel 2-

6.3.2 Quick starting CHC
Quick starting CHC, rather than waiting for the start of the next menstrual period, has the potential
advantage of reducing the time during which a woman is at risk of pregnancy; it could also reducebarriers to commencing effective contraception that could result if a woman has to wait to start her
contraceptive method.86 CHC can be quick started for medically eligible women in either of thefollowing circumstances:

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1. If pregnancy can be reasonably excluded (see Box 1) CHC can be quick started
immediately.
2. If pregnancy cannot be reasonably excluded, a high-sensitivity urine pregnancy test (HSUPT)(able to detect human chorionic gonadotrophin (hCG) levels around 20 mIU/ml) should be taken; if
negative, CHC can be quick started despite a risk of pregnancy from very recent UPSI. Almost all
the available evidence suggests no adverse impact of fetal exposure to contraceptive hormoneson pregnancy outcomes or risk of fetal abnormality. Refer to the FSRH Guideline Quick Starting
Contraception for details of studies assessed. A further HSUPT should be taken 21 days after
the last UPSI. Note that quick starting of CHC should be delayed for 5 days after ulipristal acetate(UPA) oral emergency contraception (EC).95
Box 1: Criteria for reasonably excluding pregnancy
Healthcare practitioners can be reasonably certain that a woman is not currently pregnant if
any one or more of the following criteria are met and there are no symptoms or signs of pregnancy:► She has not had intercourse since the start of her last normal (natural) menstrual period,
since childbirth, abortion, miscarriage, ectopic pregnancy or uterine evacuation for gestational
trophoblastic disease.
► She has been correctly and consistently using a reliable method of contraception. (For the
purposes of being reasonably certain that a woman is not currently pregnant, barrier methodsof contraception can be considered reliable providing that they have been used consistently
and correctly for every episode of intercourse.)► She is within the first 5 days of the onset of a normal (natural) menstrual period.
► She is less than 21 days postpartum (non-breastfeeding women).*► She is fully breastfeeding, amenorrhoeic and less than 6 months postpartum.*► She is within the first 5 days after abortion, miscarriage, ectopic pregnancy or uterine
evacuation for gestational trophoblastic disease.
► She has not had intercourse for >21 days and has a negative high-sensitivity urine
pregnancy test (able to detect human chorionic gonadotrophin (hCG) levels around
20 mIU/ml).
*See UKMEC 201696 and FSRH Guideline Contraception After Pregnancy97 forrecommendations regarding use of combined normonal contraception after childbirth.
Bleeding patterns associated with quick starting CHC
A systematic review found that bleeding patterns were similar regardless of when in the cycle CHC
was started.29
6.3.3 Summary of advice for starting CHC
Table 2 summarises when combined hormonal methods can be started and the requirements for
additional contraceptive precaution. For further details on use of CHC after pregnancy (childbirth,abortion, miscarriage, ectopic pregnancy or gestational trophoblastic disease) see the FSRH
Guideline Contraception After Pregnancy.97

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FSRH guideline: CHC

Table 2: Starting combined hormonal contraception and requirement for additional
contraceptive precautions

Circumstance

Requirement for 7 days
additional contraceptive
precautions (9 daysfor estradiol valerate/dienogest COC)

When to startNo
Women having natural Up to and including Day 5*
menstrual cycles
At any other time if it is reasonably Yes
certain she is not pregnant or a
HSUPT is negative

Requirement for
HSUPT 21 days
after last UPSINo
Consider

Women who areamenorrhoeic

At any time if it is reasonably Yes
certain she is not pregnant and/or a HSUPT is negative

ConsiderAfter LNG-EC

Immediately

Yes

Yes

After UPA-EC

5 days after taking UPA-EC

Yes

Yes

†After childbirth(breastfeeding)

From 6childbirthweeks

following Yes†After childbirth (not Without additional risk factors
breastfeeding)for VTE‡: from 3 weeks
following childbirthYesConsiderConsiderWith additional risk factors for Yes
VTE‡: from 6 weeks following
childbirth†After abortion,
miscarriage,ectopic pregnancy
or gestational
trophoblastic disease

Up to and including Day 5* No
following treatment
After Day 5* if it is reasonably Yes
certain she is not pregnant

Follow-up
pregnancy testingas per local
protocol after
these pregnancies

COC, combined oral contraception; Cu-IUD, copper-bearing intrauterine device; HSUPT, high-sensitivity urine pregnancy
test; LNG-EC, levonorgestrel emergency contraception; UPA-EC, ulipristal acetate emergency contraception; UPSI,
unprotected sexual intercourse; VTE, venous thromboembolism.
*Day 1 for estradiol-containing COC.
†See FSRH Guideline Contraception After Pregnancy.97‡In the presence of other risk factors for VTE, such as immobility, transfusion at delivery, BMI ≥30 kg/m 2, postpartum
haemorrhage, immediately post-caesarean delivery, pre-eclampsia or smoking, use of combined hormonal contraception
may pose an additional increased risk for VTE.

6.3.4 Switching to CHC from other contraceptive methods
FSRH guidance98 on switching from hormonal contraception and non-hormonal contraception to
CHC is summarised in Table 3a and Table 3b, respectively. See FSRH Guidance Switching orStarting Methods of Contraception.98

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Table 3a: Switching from hormonal contraceptive method to combined hormonal
contraception98

Switch from

SwitchtoWhen to start

Requirement
for additional
contraceptive
precaution

Notes

CHC

Another Start on day after last No
CHC
active COC, CVR or
CTP

If a hormone-free interval(HFI) is taken the need for
additional precautions andemergency
contraception
should be assessed on
an individual basis, taking
account of correct use before
the HFI. See also Table 7.

Traditional POP

CHC

Can
be
started Yes (7 days*)
immediately if the
POP has been usedconsistently
andcorrectly

The primary mode of action
is not inhibition of ovulation
andtherefore
additional
precautions are required incase ovulation occurs before
contraceptive efficacy of CHC
has been established. The
cervical mucus effect may
be maintained but there is noevidence to prove adequate
contraceptive protection.

Progestogen-only
anovulatory methods► Desogestrel-onlypill► Injectable► Implant (withinlicensed durationof use)CHC► Start on day after

LNG-IUS(within CHC
licensed duration of
use)

No

last desogestrelPOP► Start at any time
up to when therepeat injection isdue► Start at any time
up to when theimplant is due forremovalStart at any time.

The
primarymodeofaction of these methods isinhibition of ovulation. CHC
suppresses ovulation by thetime the inhibitory effect of theprevious method is lost.

Yes (7 days*)
If there has been
UPSI in the last 7
days, the LNG-IUS
should be retainedfor 7 days

CHC, combined hormonal contraception; COC, combined oral contraception; CTP, combined transdermal patch; CVR,
combined vaginal ring; LNG-IUS, levonorgestrel-releasing intrauterine system; POP, progestogen-only pill; UPSI,
unprotected sexual intercourse.
*9 days estradiol valerate/dienogest pill.

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FSRH guideline: CHC

Table 3b: Switching from non-hormonal contraceptive method to combined hormonal
contraception98
Requirement
for additional
contraceptive
precaution

Switch from

Switch to

When to start

Cu-IUDCHC

Up to Day 5 of menstrual No
cycle(Day 1 estradiol COC)

Cu-IUD can be removed atthat time.

At any other time during Yes (7 days)*the menstrual cycle or if
amenorrhoeic

AND retain Cu-IUD for 7
days after last UPSI.

CHC
Non-hormonal
method(otherthan a Cu-IUD)

Notes

Up to and including Day No
5 of menstrual cycle(Day 1 estradiol COC)
At any other timeYes (7 days*)

Consider follow-up pregnancy
test.
If amenorrhoeic, a negative
HSUPT should be obtained
before starting CHC.

CHC, combined hormonal contraception; COC, combined oral contraception; Cu-IUD, copper intrauterine device; HSUPT,
high-sensitivity urine pregnancy test.
*9 days estradiol valerate/dienogest pill.

7. How effective is CHC?
7.1 Contraceptive effectiveness of CHC
Key information

C

Contraceptive effectiveness of all CHC is similar.

✓

If used perfectly, CHC is very effective for contraception. With typical use, CHC isless effective for contraception than long-acting reversible contraception (LARC).

Clinical recommendation✓

Women requesting CHC should be informed about the effectiveness (with both
typical and perfect use) of CHC and other contraceptive methods, including thesuperior effectiveness of LARC.

All CHC methods require consistent and correct use to provide effective contraception.
Method adherence can vary widely depending on user characteristics such as age,socioeconomic status, desire to prevent or delay pregnancy, and culture. A Cochrane
Review comparing standard use of the combined pill, patch and ring concluded thatthese methods are of similar effectiveness.99 See Section 6.2.2.

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FSRH guideline: CHC

With perfect use of CHC (following directions for use) it has been estimated that 0.3% of users
experience an unplanned pregnancy during the first year of use. In contrast, the first-year failure
rate associated with typical use of CHC (actual use including inconsistent or incorrect use) has
been estimated to be around 9%.100 This estimate uses data from the US National Survey of Family
Growth.101–103 Reported CHC contraceptive failure rates vary. It is noted that women who knowthat they are taking part in a study might comply differently with pill-taking. The Contraceptive
Choice project in the USA reported a first-year failure rate for combined pill, patch and ring of 4.8%
among women who were provided with their choice of contraceptive method free of charge. 104 The
International Active Surveillance of Women Taking Oral Contraceptives study in the USA reported a
1-year failure rate of 3.5%, based on 1634 unintended pregnancies during 73 269 woman-years oforal contraceptive pill exposure.105 Secondary analysis of data from the European Active Surveillance(EURAS) study of OC (which included (112 659 woman-years of OC exposure and 545 unplanned
pregnancies) reported a 0.75% failure rate (95% CI 0.68–0.82) for OC in the first year of use.106
Table 4 compares the effectiveness of currently available contraceptive methods, with the mosteffective LARC methods highlighted. Given the relatively high estimated failure rates associated withtypical use of CHC, the GDG recommends that women requesting CHC should be informed about
the effectiveness of different contraceptives, including LARC.107 The failure rate of LARC is less than
1% with both typical and perfect use as it is not subject to user failure.
Acceptability of LARC methods for women who initially request short-acting contraception
Some women who request OC can find LARC methods an acceptable alternative; in a US study,
916 women aged 18–29 years who requested short-acting contraception were given the optionof receiving their short-acting method in the usual way or being randomised to receive either ashort-acting method or a LARC method of their choice free of charge. A total of 392 women agreed
to randomisation. Amongst women randomised to LARC, method acceptability and continuation
rates were high and unintended pregnancy rates significantly lower than for women choosing or
randomised to short-acting methods.108 LARC methods should be discussed, but women should not
be pressured into using any particular method of contraception.
Table 4: Percentage of women experiencing an unintended pregnancy within the first yearof use with typical use and perfect use (modified from Trussell) 100
MethodTypical use (%)(estimated)

Perfect use (%)

No method
Fertility awareness-based methods
Female diaphragm

85
24
12

85
0.4–5
6

Male condom
Combined hormonal contraception*

18
9

2
0.3

Progestogen-only pill
Progestogen-only injectable

9
6

0.3
0.2

Copper intrauterine device
Levonorgestrel intrauterine system
Progestogen-only implant

0.8
0.2
0.05

0.6
0.2
0.05

Female sterilisation
Vasectomy

0.5
0.15

0.5
0.1

Long-acting reversible contraception/contraceptive methods in bold type.
*Includes combined oral contraception, transdermal patch and vaginal ring.

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FSRH guideline: CHC

7.2 What can affect contraceptive effectiveness of CHC?
As noted in Section 7.1, effectiveness of CHC is highly dependent on correct and consistent use.
Other factors that could affect contraceptive effectiveness are considered below.
7.2.1 Is contraceptive effectiveness of CHC affected by obesity/weight?
Key information

C

Most evidence suggests no association between weight/BMI and effectiveness of
COC.

D

Limited evidence suggests a possible reduction in patch effectiveness in women≥90 kg.

Note that use of CHC is UKMEC 3 for use by women with BMI ≥35 kg/m2. UKMEC recommendations
relate to safety of use rather than to effectiveness.
Evidence relating to the effect of body weight/BMI on effectiveness of CHC is limited to observational
studies in which height, weight and pregnancy are often self-reported and potential confounding
factors such as contraceptive compliance and frequency of intercourse are unknown. Most studies
include relatively few women in the highest weight/BMI categories. There is limited evidence thatovarian activity in the HFI could be more pronounced in obese women. 41,42 See Section 6.2.2
regarding studies considering ovarian activity in the HFI as an indication of risk of pregnancy.
A 2017 systematic review109 reported that 10 out of 14 studies of COC identified did
not report a difference in effectiveness by body weight or BMI; in the remaining fourstudies, the magnitude of the reported difference in COC failure was very small.
Differences between different COC formulations could not be distinguished. A 2016
Cochrane Review110 concluded that in general the evidence identified did not indicate
an association between increasing body weight or BMI and effectiveness of COC.

Evidencelevel 2+The limited evidence identified109 suggests that increasing body weight and BMI may
contribute to decreasing effectiveness of the CTP. No direct evidence regarding bodyweight/BMI and effectiveness of the contraceptive ring was identified.

Evidencelevel 2-The GDG (in line with the Summary of Product Characteristics for the CTP) 10 notes that
contraceptive effectiveness of the CTP could be decreased in women weighing ≥90 kg, therefore
it is recommended that additional precautions or an alternative method should be advised for
women ≥90 kg.
7.2.2 Is contraceptive effectiveness of CHC affected by bariatric surgery?
Clinical recommendation

D

Women who have had bariatric surgery should be advised that the effectivenessof COC could be reduced.

There are theoretical concerns that both malabsorptive and restrictive bariatric procedures Evidence
could decrease the absorption of oral contraceptives. 111,112 A systematic review113 level 2identified one small prospective cohort study114 in which two of nine women using COC
after biliopancreatic bypass surgery (both with significant diarrhoea) became pregnant
in the 2 years following surgery; a second descriptive study115 reported no pregnancies
among COC users (number unknown) in the 2 years after a gastric banding procedure.

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One pharmacokinetic study116 reported lower serum progestogen levels afteradministration of oral progestogen for morbidly obese women (BMI ≥40 kg/m 2) after
bypass surgery compared with healthy non-obese women; the difference could however
be attributable to body weight. In contrast, a second pharmacokinetic study117 reported
higher serum progestogen levels after administration of an oral combined estradiol/progestogen preparation in 12 morbidly obese women after bypass surgery than in six
morbidly obese women who had not had surgery.

Evidencelevel 2-The evidence is too limited to make a definite recommendation regarding the effectiveness of COC
after bariatric surgery. The GDG recommends that women who have had bariatric surgery should
be advised of potential reduced effectiveness of COC and should consider a non-oral method ofcontraception.
7.2.3 What drug interactions are important to consider in relation to CHC?
Serum levels of contraceptive hormones may be altered by concomitant use of other drugs; contraceptive
effectiveness could be affected. Hormonal contraceptives may themselves alter serum levels of otherdrugs that a woman is taking, with potential adverse effects. Drug interactions should therefore always
be considered when prescribing CHC and when prescribing other drugs for women who are using CHC.
Refer to the FSRH Guideline Drug Interactions with Hormonal Contraception.118
Enzyme-inducing drugs
Clinical recommendations

D

Women using enzyme-inducing drugs should be informed that the contraceptive
effectiveness of CHC could be reduced during use of the enzyme-inducer and for
28 days after stopping.

D

Women using enzyme-inducing drugs should be offered a reliable contraceptive
method that is unaffected by enzyme-inducers.

FSRH Guideline Drug Interactions with Hormonal Contraception118 notes that hepatic Evidence
enzyme-inducing drugs increase the metabolism of estrogens and progestogens, level 4
which could reduce the contraceptive effectiveness of all CHC methods. Women
using enzyme-inducing drugs should be advised to switch to a contraceptive method(e.g. intrauterine methods or the progestogen-only injectable) that is unaffected byenzyme-inducers.
It is established practice that if, after advice to switch contraceptive method, a woman
wishes to use COC concomitantly with an enzyme-inducing drug (with the exceptionof rifampicin or rifabutin which are potent enzyme-inducers) use of a minimum 50 μg(30 μg + 20 μg) EE monophasic combined pill may be considered during use of the
enzyme-inducer and for a further 28 days after stopping. A continuous or tricycling
regimen plus a shortened pill-free interval of 4 days should be used. Breakthroughbleeding could indicate low serum EE concentrations. Dose of EE can exceptionally be
increased up to a maximum of 70 μg after specialist advice. It is not known how suchusage affects risk of VTE. The use of two patches or two rings is not recommended.

Evidencelevel 4

Short-term use of enzyme-inducing drugs (<2 months) can be managed more flexibly
than longer-term use. Continuing use of CHC with consistent and careful use of condoms
may be appropriate in this situation.

Evidencelevel 4

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FSRH guideline: CHC

Lamotrigine
Clinical recommendation

D

Women taking lamotrigine should be advised that CHC may interact with lamotrigine;
this could result in reduced seizure control or lamotrigine toxicity. The risks of using
CHC could outweigh the benefits.

Serum levels of lamotrigine can be reduced by CHC. 119–124 A case series122 reported
increased seizure frequency in four women with reduced lamotrigine levels following
the initiation of COC. Data120 demonstrate increased lamotrigine levels during the
HFI and increased lamotrigine side effects have been reported on cessation of
CHC.119

Evidencelevel 3

Lamotrigine is not thought to be an enzyme-inducing drug, but the manufacturer
advises that contraceptive effectiveness of CHC could be reduced by concurrent useof lamotrigine. This advice is based on a study125 of 16 women using 30 μg EE/150 μg
LNG and lamotrigine for 6 weeks which found a modest increase in levonorgestrel
clearance and changes in serum FSH and LH. The clinical significance in termsof contraceptive effectiveness is unknown. An earlier study of women using 30 μg
EE/150 μg LNG and lamotrigine for 10–14 days reported a statistically non-significant
decrease in the mean plasma concentration of EE but no change in LNG levels; noovulation occurred and no change in menstrual patterns was observed.126
The risk of using CHC may outweigh the benefit for women using lamotrigine, given
the potential risk of reduced seizure control whilst taking CHC, and potential forlamotrigine toxicity in the HFI. It is advised that alternative contraception should beconsidered.118

Evidencelevel 4

Antibiotics (non enzyme-inducing)
Key information

D

Additional contraceptive precautions are not required when antibiotics that do not
induce enzymes are used in conjunction with CHCs.

Most broad-spectrum antibiotics are non-enzyme-inducing and it is established FSRH
guidance118 that no additional contraceptive precaution is required unless the antibiotics(and/or illness) cause vomiting or severe diarrhoea (see Section 7.2.4).127,128

Evidencelevel 4

Progestogen receptor modulators
Clinical recommendation

D

20

Women should be advised to wait 5 days after taking UPA-EC before starting CHC.
Women should be made aware that they must use condoms reliably or abstain
from sex during the 5 days waiting and then until their contraceptive method iseffective.

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FSRH guideline: CHC

UPA is a selective progesterone receptor modulator. Limited evidence from biomedical
studies129,130 suggests that effectiveness of oral hormonal contraception is not reducedby concomitant use of UPA-EC. Biomedical studies have demonstrated that starting an
EE/LNG COC131 or a desogestrel POP129 soon after UPA 30 mg given for emergency
contraception (UPA-EC) reduces the ability of UPA-EC to delay ovulation and could
therefore reduce the effectiveness of UPA-EC. The FSRH Guideline Emergency
Contraception recommends that after UPA-EC, commencement of CHC is delayedfor 5 days (at least 120 hours) after UPA-EC has been given.95 This ensures that
the UPA-EC is as effective as possible in preventing pregnancy resulting from theepisode(s) of UPSI for which it was taken. After the 5 days waiting, CHC can be started
with advice to use additional contraceptive precautions for the following 7 days.

Evidencelevel 4

Theoretically, there could be an interaction between CHC and UPA taken for management offibroids.
7.2.4 Severe diarrhoea or vomiting
Clinical recommendation✓

Women using COC should be advised that contraceptive effectiveness could be
reduced by vomiting or severe diarrhoea.

The general advice for women using oral contraceptives is to follow the instructions formissed pills if vomiting occurs within 3 hours of taking COC or severe diarrhoea occurs
for >24 hours. Women should be advised to consider non-OC if diarrhoea or vomiting
persist.118 Some drugs have the potential to reduce the effectiveness of contraceptives
indirectly by causing diarrhoea or severe vomiting.

Evidencelevel 4

8. Incorrect use of CHC
Missing CHC removes the suppressive effects of contraceptive steroids on ovarian follicle growth
thereby risking ovulation and conception. Women using CHC who miss pills or make mistakeswith their CVR or CTP are at increased risk of pregnancy compared with women who use CHC
perfectly.
Repeated attempts to re-write ‘missed pill rules’ which more accurately reflect the evidence haveconcluded that simple rules are more likely to be followed. As a result, advice on what to do when pills(or other methods of CHC) are taken incorrectly is overcautious. Nevertheless a simple, overcautious
rule to which everyone agrees is better than complicated rules that are not followed. See FSRH
Guidance on Incorrect Use of CHC.
8.1 Combined oral contraception
A COC pill is missed if it is not taken in the 24 hours after it should have been taken. Missing a single
COC pill is insufficient to reverse ovarian suppression; however, missing several pills or extending
the HFI by missing pills at the end of a packet or forgetting to restart the new packet on time could
theoretically increase risk of ovulation.
Many observational studies have attributed pregnancy during COC use to missed pills, but evenwhen daily diaries of pill-taking are kept during studies, information on dosing errors is likely to beinaccurate.132 One study of typical COC use in which 82 new users of a standard 21/7 COC were
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FSRH guideline: CHC

given their pill supply in an electronic dispenser which recorded whether or not pills had been takenfrom the packet showed that during 3 months of COC use 57% of women missed an average ofthree or more pills each cycle but there were no pregnancies. 132 Evidence from biomedical studies
that have assessed ovarian activity associated with missed pills is limited by the fact that studies are
small and use different markers to define ovulation.
Missed pills in weeks adjacent to the HFIThe available evidence for risk of ovulation if the HFI is extended is presented in Section 6.2.2. It isconsidered that missing pills in the first week of pill taking after the HFI or in the week prior to the HFI
effectively extends the HFI; missed pill rules reflect this.
Missed pills in weeks not adjacent to the HFI
Two small studies that examined ovulation risk if pills are missed in weeks not adjacent to the HFI
indicated that ovarian activity is suppressed after seven consecutive days of COC. 29 A systematic
review39 concluded (on the basis of 10 small, biomedical studies) that missing one to four consecutive
pills on days not adjacent to the HFI resulted in little follicular activity and low risk of ovulation. The
review identified two studies comparing missed pills containing either 20 or 30 µg EE which reported
more follicular activity when 20 µg EE pills were missed; differences in ovulation rates did not varywith the progestogen component of COC.
No studies have explored the effect of missed pills among women using COC containing natural
estrogens. Providers should refer women who use these brands to the advice given on thelabel.
See FSRH Guidance on Incorrect Use of CHC.
8.2 Combined transdermal patch
A systematic review39 included two studies that examined the CTP: a pharmacokinetic study foundthat serum concentrations of EE and norelgestromin remained within the reference range forcontraceptive efficacy even after extending patch use for 3 days;133 in the second study, little follicular
activity and low risk of ovulation were observed when use of a patch was extended to 10 days or apatch was removed after 7 days of use and not replaced for 3 days thereafter. 134 No studies were
found on extending the patch-free interval.
See FSRH Guidance on Incorrect Use of CHC.
8.3 Combined vaginal ring
A systematic review39 included six studies examining dosing errors with the CVR: three observational
studies135–137 provided limited evidence suggesting that extension of the ring-free interval for up toan additional 48 hours does not increase the risk of pregnancy; one study 138 reported that after adeliberately extended HFI which was continued until a 13 mm ovarian follicle developed, ovarianfunction and further follicular growth was re-suppressed when a new ring was inserted; in anotherstudy inhibition of ovulation was maintained after deliberately leaving the ring in place for up to
5 weeks, suggesting that the suppressive effects of the CVR last a considerable time.
See FSRH Guidance on Incorrect Use of CHC.

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FSRH guideline: CHC

Women who frequently miss COCs or make repeated mistakes with a CTP or CVR should be advised
to consider an alternative contraceptive method that is less dependent on the user to be effective(e.g. LARC methods).

9. Non-contraceptive health benefits associated with CHC use
Key information✓

Use of CHC for contraception may also be associated with non-contraceptive healthbenefitsB

Use of CHC can reduce heavy menstrual bleeding (HMB) and menstrual pain andimprove acne.

C

Use of CHC may be beneficial for women with premenstrual syndrome (PMS)
symptoms.

A

Use of CHC (particularly continuous CHC regimens) can reduce risk of recurrenceof endometriosis after surgical management.

B

CHC can be used for management of acne, hirsutism and menstrual irregularities
associated with polycystic ovary syndrome (PCOS).

CCHC use is associated with a significant reduction in risk of endometrial and ovariancancer that increases with duration of CHC use and persists for many years after
stopping CHC.

C

Use of CHC is associated with a reduced risk of colorectal cancer.

9.1 Heavy menstrual bleeding
The National Institute for Health and Care Excellence (NICE) Heavy Menstrual Bleeding
guideline indicates that COC can be used for management of HMB but would generally
be second-line after the LNG-releasing intrauterine system (IUS).139 Evidence from
RCTs and non-randomised trials consistently reports a reduction in menstrual blood
loss in women with HMB using CHC.140–143

Evidencelevel 1+Further evidence from two RCTs142,143 that compared CVR with COC for the management Evidenceof HMB suggests that they are equally effective, and that CVR could offer better cycle level 1control and adherence to correct use.
9.2 Menstrual pain
Limited evidence identified in two systematic reviews 144,145 suggests that COC
reduces menstrual pain. There is no robust evidence for a differential benefit between
different preparations of COC including different estrogen dose. One RCT 146 reported
that CVR is effective in treatment of idiopathic chronic pelvic pain. A small number of
RCTs147–149 suggest that extended use of COC is effective for the treatment for primarydysmenorrhoea and may be superior to the traditional cyclic regimen, at least in the
short term.

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Evidencelevel 1-

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FSRH guideline: CHC

9.3 Acne
Evidence
Evidence suggests that use of CHC can improve acne vulgaris. A Cochrane Review150
updated in 2012 concluded that COCs are effective in reducing facial acne lesions. The level 1review included nine placebo-controlled trials, all demonstrating that COC reduced acne
lesion counts, severity grades and self-assessed acne compared to placebo. Data werelimited for comparative effectiveness of different COC; overall few differences between
the COCs studied were identified in terms of their effectiveness in treating acne. The
authors noted that the lack of use of standardised methods for assessing acne prevents
the pooling of results across trials and complicates their interpretation. Two further
RCTs151,152 also reported improvement in acne outcomes with COC use.
Two small observational studies have reported that acne improved for some women
during CTP use.153,154 A Cochrane Review99 which included three RCTs found that acne
was reported as a side effect less often by CVR users than by COC users.

Evidencelevel 2-

9.4 Premenstrual symptoms
Based on the limited available evidence (presented below) the GDG recommends that symptoms
of premenstrual syndrome (PMS)/premenstrual dysphoric disorder (PMDD) could be improvedin women who use COC for contraception. A continuous regimen may be considered. The 2016
Royal College of Obstetricians and Gynaecologists (RCOG) Green-top Guideline Management ofPremenstrual Syndrome155 recommends that EE/DRSP COC should be considered a first-line
pharmaceutical intervention for management of PMS.
9.4.1 EE/DRSP COC for management of premenstrual symptoms
Addressing EE/DRSP COC specifically, a 2012 Cochrane Review of RCTs156 concluded“Drospirenone with EE 20 μg COC may help treat premenstrual symptoms in women withpremenstrual dysphoric disorder (PMDD). However, a powerful placebo effect was evident:
in one trial, symptoms were reduced for 48% of the drospirenone COC group versus
36% of the placebo group. The difference may not be clinically significant. Furthermore,
effectiveness after three cycles is unknown. Little evidence exists for treating less severe
symptoms or whether a drospirenone COC works any better than other COCs.”
Subsequent to the Cochrane Review a small RCT demonstrated no significant
difference between placebo and EE/DRSP COC taken either cyclically or continuously
for management of PMDD.157 The authors commented on the marked placebo responsethat was observed; a second small RCT suggested that COC containing either DRSP ordesogestrel could reduce PMS symptoms, but there was no placebo arm. 158
9.4.2 Other COC for management of premenstrual symptoms
Evidence from RCTs for CHC other than EE/DRSP is sparse and inconclusive, but suggeststhat other COC formulations could also be associated with symptom improvement in womenwith PMDD.159,160 The findings of the observational studies identified161–166 are limited bysmall study size, short duration of observation, lack of a verified symptom assessment tool,and lack of a comparator group that was not using hormonal contraception.
9.4.3 Extended COC regimens for management of premenstrual symptoms
A cohort study (and its extension) commenced 114 women on an EE/DRSP COC for
two 21/7 cycles and then changed them to a continuous regimen of the same COC.71,162
102 women completed 168 days and 80 completed a year of extended use. The
study reported that PMS symptoms improved significantly with the extended regimen
compared to cyclical use.
24

Evidencelevel 1-

Evidencelevel 1-

Evidencelevel 2-

Evidencelevel 2-

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FSRH guideline: CHC

9.5 Vasomotor symptoms
Overall, limited evidence suggests that use of COC can help alleviate vasomotor symptoms inperimenopausal women.
A placebo-controlled, double-blind, randomised, parallel group study167 including
132 perimenopausal women found that the frequency and severity of hot flushes
decreased in the group treated with a low-dose, monophasic COC (20 μg EE/
norethisterone) compared to placebo. Among the 65% of subjects who experienced atleast one hot flush daily (38 COC, 36 placebo), COC users experienced approximately
50% fewer hot flushes over the 6-month study period than placebo users. However,statistical significance was not reached due to wide variability. Quality of life assessments
indicated significant improvements in the COC treatment group.

Evidencelevel 1-A randomised, double-blinded study168 of 56 women in their 40s presenting with mooddisorders and/or hot flushes reported that the addition of 5 days of estrogen during
the HFI improved the vasomotor symptoms of perimenopausal women using COC.
Thirty-three women were randomised to the estrogen group (21 tablets containing 20 μg
EE/desogestrel, followed by two placebo tablets and five tablets containing 10 μg EE)
and 23 women to the placebo group (21 tablets containing 20 μg EE/desogestrel andthen seven placebo tablets). During 3 months of use, women in the estrogen groupreported a significant decrease in vasomotor symptoms (p<0.04) compared to theplacebo group.

Evidencelevel 1-A 3-year, prospective cohort study169 comparing 100 perimenopausal women
treated with a triphasic COC (30/40/30 μg EE and 0.05/0.075/0.125 mg LNG) witha similar number of age-matched untreated women reported that all women in thetreatment group had complete relief of vasomotor symptoms after 3 months’ use;
90% achieved this within 2 months. In contrast, 60% of women in the untreatedgroup had no improvement in vasomotor symptoms during the 3-month observation
period.

Evidencelevel 2+

Clearly there is a great deal more evidence for use of hormone replacement therapy (HRT) for
vasomotor symptoms170. Decisions about whether it is more appropriate for a woman aged under 50
to use HRT plus additional contraception or CHC alone must be made on an individual basis, taking
into consideration the safety of use of HRT compared to that of CHC.
9.6 Bone healthA Cochrane Review of RCTs171 concluded that COC use does not appear to negatively
affect BMD. A Cochrane Review of observational studies172 reported that the evidence
identified does not indicate an overall association between oral contraceptive use andfracture risk.
AdolescentsSome studies have suggested that in adolescents, accrual of BMD could be lower inusers of COC than in non-users of hormonal contraception.173–175 One study174 which
randomised 487 girls aged 12–19 years to use of a 30 µg EE/LNG COC either as a
traditional 21/7 regimen or as an extended 84/7 regimen compared lumbar spine BMD
after 12 months of use to an unmatched reference group of non-users of hormonal
contraception. Increase in BMD was significantly greater among non-users than for thoseusing 21/7 COC, but not for users of the extended regimen 84/7 COC.
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FSRH guideline: CHC

Perimenopausal women
Evidence
Note that use of CHC by women aged over 50 years is not generally recommended level 1(see Section 15.1.1). Evidence suggests that COC could be beneficial in preventing
the decline in BMD in perimenopausal women. Five prospective cohort studies169,176–179(four studies from the same authors) compared perimenopausal women given various
low-dose COC for 2 or 3 years (n=16 to n=100) with non-COC-using controls; thestudies reported no change or increase in BMD amongst COC users and reduced
BMD in the control groups. A very small RCT180 which compared eight perimenopausal
women given low-dose COC with nine matched controls over 3 years reported a slight,
non-significant increase in BMD in COC users and a significant reduction in BMD incontrols. Evidence from a large RCT181 investigating use by perimenopausal women of
EE/NET preparations containing much lower doses of EE (1–10 µg) than those in COC
also suggests a protective effect of EE/progestogen on BMD in the perimenopause.
The clinical significance of these findings in terms of fracture risk is uncertain.

9.7 Endometriosis
NICE Guidance Endometriosis: Diagnosis and Management182 and European Society of Human
Reproduction and Embryology (ESHRE) Guideline Management of Women with Endometriosis183
indicate that CHC has an important role in the management of endometriosis.
Studies have shown that CHC therapy is effective, safe and well-tolerated by women withendometriosis.182,184 A meta-analysis185 reported a significantly higher rate of remission
from endometriosis symptoms and a lower rate of recurrence in women taking COC
after surgery compared with surgery alone.

Evidencelevel 1++

Evidence suggests that a continuous rather than a cyclical COC regimen isadvantageous in the management of endometriosis. One systematic review 186
showed that after conservative surgery, continuous COC use was associated with asignificant reduction in dysmenorrhoea and a longer period before dysmenorrhoea
recurred compared with cyclical use. One further RCT 187 also reported a reduction in
endometriosis-associated pelvic pain, an improvement in sexual activity and qualityof life in women on a EE/dienogest continuous regimen compared to a 21/7 regimen.
Another systematic review188 reported that a significantly lower postoperative
dysmenorrhoea recurrence rate was observed in continuous compared to cyclical
COC users; however, this study did not identify significant differences in dyspareunia,
non-menstrual pelvic pain, or endometriosis recurrence rates between continuousand cyclical users.
Women with endometriosis who wish to use OC may also be advised aboutprogestogen-only contraception, which is an effective first-line alternative formanagement of endometriosis symptoms and reduction of recurrence risk, but
avoids any estrogen-associated health risks.184,189,190

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9.8 Polycystic ovary syndrome
The Endocrine Society Clinical Practical Guideline Diagnosis and Treatment of
Polycystic Ovary Syndrome191 recommends CHC (including the CTP and CVR) for
first-line treatment of menstrual irregularity, acne and hirsutism in women with PCOS.
The guideline notes however that “there are insufficient data to define the optimal
duration of treatment”.

Evidencelevel 1+The Endocrine Society also recommends CHC as the first-line treatment foradolescents requiring treatment for acne, hirsutism or menstrual bleeding irregularities
due to anovulation and for pre-menarchal girls with clinical and biochemical evidenceof hyperandrogenism in the presence of advanced pubertal development (i.e. TannerStage IV breast development).191
With regard to management of acne and hirsutism, there is no good evidence for any
differential effectiveness of CHC containing different progestogens. Recent studies
have focused on the effects of COC containing DRSP, an anti-androgenic progestogen.
A systematic review192 which included 18 RCTs of EE/DRSP versus standard treatment
options concluded that DRSP was effective in treating the symptoms of PCOS. Recent
evidence suggests benefit with use of 20 µg EE/DRSP COC. 193,194
9.9 Effect of CHC use on cancer risk and mortality
A large number of epidemiological studies (and systematic reviews and meta-analysis ofthese studies) have informed our understanding of the association between use of COC andrisk of cancer. Long-term follow-up in the Royal College of General Practitioners (RCGP) Oral
Contraception Study195 indicates a statistically non-significant 4% reduced risk of any cancer(incidence rate ratio (IRR) 0.96; 99% CI 0.9–1.03) associated with ever-use of OC compared withnever-use.
9.9.1 Endometrial cancer
Systematic review and meta-analyses of observational studies196,197 indicate that
OC use is associated with a reduced risk of endometrial cancer that correlates withduration of use and persists for many years after cessation. A recent meta-analysis197 of
36 international epidemiological studies found that every 5 years of OC use is associatedwith a relative risk of 0.76, resulting in a 50% reduction in risk of endometrial cancer
with 10–15 years of use. A meta-analysis reported a persistent protective effect for as
long as 30 years after cessation of OC; no significant differences were observed whencomparing OC doses and formulations.197
In line with this, the RCGP Oral Contraception Study 195 reported that compared tonever-users of OC, the risk of endometrial cancer for ever-OC-users is reduced by
34% (IRR 0.66; 99% CI 0.48–0.89). Similarly, recently published data from a large US
prospective cohort study198 indicate a significant 34% reduction in risk of endometrial
cancer associated with ≥10 years OC use compared to never-use or use for less thana year; the greatest risk reduction was observed amongst smokers and women withobesity.

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9.9.2 Ovarian cancer
A systematic review of observational studies199 reported a reduction in risk of ovarian Evidence
cancer in ever-users of OC compared to never-users. The meta-analysis199 found level 2+that the protective effect is duration-dependent, with women who have used OC forat least 10 years having a 50% reduction in incidence of ovarian cancer. A review ofpublished meta-analyses200 reported that the protective effect has been observed inwomen both with and without a genetic predisposition to ovarian cancer, increases
with increasing duration of OC use and persists for at least 30 years after cessationof use. A subsequently published case-control study201 which included 1632 casesand 2340 controls suggested that there could be greater protection conferred to those
who start OC before the age of 35 years than those who start after age 35 years. The
UK RCGP Oral Contraception Study195 reported that, compared to never-users ofOC, the risk of ovarian cancer of ever-OC-users is reduced by 33% (IRR 0.67; 99%
CI 0.5–0.89). Recently published data from a large US prospective cohort study 198
indicate a significant 40% reduction in risk of ovarian cancer associated with ≥10 years
of OC use compared to never-use or use for less than 1 year.
BRCA gene mutation carriers
On the basis of evidence from case-control studies that include small numbers ofcases, three systematic reviews with meta-analysis202–204 have concluded that amongst
BRCA carriers, use of OC (COC or POP not specified, but majority likely to be COC)
is associated with reduced risk of ovarian cancer with use, proportional to the durationof use. The evidence is stronger for BRCA1 carriers but exists for both BRCA1 andBRCA2. See Section 10.4.
9.9.3 Colorectal cancer
Evidence from three meta-analyses196,205,206 of data from observational studies
suggests that ever-OC-users have a reduced risk of colorectal cancer compared tonever-OC-users. In line with the findings of the other two studies, the most recent
meta-analysis205 which included 12 cohort studies and 17 case-control studies witha total of 15 790 cases of colorectal cancer reported a summary relative risk (RR)
for colorectal cancer of 0.82 (95% CI 0.76–0.88) for ever-users versus never-usersof OC after adjustment for confounding lifestyle factors. More recently publisheddata198 from a large prospective cohort study suggested no significant association
between OC use and risk of colorectal cancer. The UK RCGP Oral Contraception
Study195 reported that compared to never-users of OC, the risk of colorectal cancerof ever-users is reduced by 19% (IRR 0.81; 99% CI 0.66–0.99).

Evidencelevel 2+9.9.4 Mortality
A meta-analysis207 of eight cohort studies involving 217 868 women and 40 570 deaths did Evidence
not find a significant association between ever-use of OC and all-cause mortality (hazard level 2+
ratio (HR) 0.94; 95% CI 0.87–1.02) regardless of duration of OC use and time since lastuse. The UK RCGP Oral Contraception Study, a large prospective UK cohort study with 1.3
million woman-years of observation, found that women who had ever used OC had a 12%
lower risk of all-cause mortality when compared with those who had never used OC.208 In
addition to reduced mortality, ever-users of OC were observed to have a non-significant
reduction in overall cancer risk, and for some cancers this protective effect persisted for
decades following cessation of OC.195 Reassuringly, over a 44-year period of follow-up, noincreased cancer risk was observed later in life for women who had ever used OC.
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10. Health risks associated with CHC use
Clinical recommendation✓

Women should be informed about the health risks associated with use of CHC.

10.1 Venous thromboembolism (VTE) (including deep vein thrombosis and pulmonary
embolism)
Key information

C

Current use of CHC is associated with increased risk of VTE; some CHC formulations
are associated with a greater risk of VTE than others, dependent on progestogen
type and estrogen dose.

Clinical recommendation

C

Women should be advised that use of CHC is associated with an increased risk of
VTE, but the absolute risk of VTE for an individual CHC user remains very small.

Evidence from observational studies suggests that current use of COC is associated witha 3- to 3.5-fold increase in VTE risk compared with non-use of CHC.209–211 It is important
to note that despite this increased risk, the number of VTE events in women using
CHC remains very small; the absolute risk of VTE during use of CHC is estimated by
the European Medicines Agency to be between 5 and 12 per 10 000 women per year ofuse compared to 2 per 10 000 non-CHC users per year.212 Of the small number of VTE
events that do occur during use of CHC, approximately 1% are fatal. 213

Evidencelevel 2+

VTE risk is lower during CHC use than during pregnancy and the postpartum period.214–221
By reducing rates of unplanned pregnancy, CHC use lowers the overall rate of VTE in
the population in comparison to populations without access to effective contraception.222
Risk of VTE is highest in the months immediately after initiation of CHC 223–226 or whenrestarting after a break of at least 1 month.223 The risk then reduces over the first yearof use and remains stable thereafter.224,226–229 Frequent stopping and starting of CHC istherefore discouraged.

Evidencelevel 2+UKMEC 2016 gives recommendations regarding safety of use of CHC by women with characteristics
or medical conditions (such as increasing age, higher BMI and thrombophilia) that put them atincreased risk of VTE.96
10.1.1 Effect of progestogen type on VTE risk
A systematic review identified no relevant RCTs. 230 Meta-analysis230 of the data fromobservational studies (which may be subject to confounding and prescribing bias)
indicated that use of low-dose COC (<50 µg EE) containing cyproterone acetate,desogestrel, gestodene or DRSP was associated with a significant 1.5- to 2-fold riskof VTE compared to use of COC containing LNG. Norgestimate COC was found to be
associated with similar VTE risk to LNG COC. These findings are consistent with thoseof other recent meta-analyses which suggest that use of some third-generation COC isassociated with greater VTE risk than use of second-generation COC (differences are
not always statistically significant).209,210,231,232

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In 2014, the EMA published estimated figures for absolute risk of VTE in users of CHC (see Table 5).
Note that estimates of background VTE risk in women of reproductive age vary. The EMA estimatesthat the incidence of VTE among women who are not using CHC and are not pregnant is about
2 per 10 000 woman-years233; a large Danish cohort study234 reported a VTE incidence of 3.7 per
10 000 woman-years for non-users of CHC; a 2007 literature review235 concluded that the overall VTE
incidence in all women of reproductive age is likely to be in the range of 5–10 per 10 000 woman-years.
Table 5: European Medicines Agency estimated risk of developing a venous
thromboembolism (VTE) in a year according to type of combined hormonal contraception(CHC) used212
Type of CHC used

Risk of developing a VTE in a year
(incidence in 10 000 women)

Women not using combined hormonal pill/patch/ring and not pregnant~2

Women using CHC containing levonorgestrel, norethisterone or
norgestimate~5–7

Women using CHC containing etonogestrel or norelgestromin~6–12

Women using CHC containing drospirenone, gestodene ordesogestrel*~9–12*Evidence suggests that co-cyprindiol is associated with similar VTE risk to combined oral contraceptive containing
drospirenone, gestodene or desogestrel.230

10.1.2 Effect of dose of EE on VTE risk
Available studies are limited by their observational nature and the small numbers of VTE events insome study groups. COC preparations that have been studied vary with respect to progestogen as
well as the dose of EE; it is therefore difficult to compare the effect of EE dose on VTE risk.
A systematic review and meta-analysis suggested that VTE risk among users of COC isdependent on the dose of EE, with higher EE dose being associated with greater VTE
risk.209,236 The meta-analysis209 concluded that a 50 µg EE/LNG COC was associatedwith RR for VTE of 2.1 (95% CI 1.4–3.2) and 2.3 (95% CI 1.3–4.2) compared with a
30 µg and 20 µg EE/LNG COC, respectively. VTE risk was significantly greater for
30 µg EE than 20 µg EE COC containing gestodene, but not those containing LNG ordesogestrel.

Evidencelevel 2+

Subsequent to the systematic review, a large French database study indicated a lower
risk of pulmonary embolism associated with COC containing 20 µg EE than COC with
30–40 µg EE (adjusted RR 0.75; 95% CI 0.67–0.85).237
10.1.3 Effect of estrogen type on VTE risk
Most COC contain EE. However, COC are now available that have estradiol as their estrogencomponent, in combination with either dienogest or nomegestrol acetate. Direct evidence regarding
risk of VTE associated with use of these COC is limited. A large cohort study in the USA and Europe
which observed 47 VTE events amongst 50 203 new COC users followed for a mean of 2.1 years
reported adjusted HRs of 0.4 (95% CI 0.2–1.0) and 0.5 (95% CI 0.2–1.5) for users of estradiol
valerate/dienogest compared to users of “other COC” and EE/LNG COC, respectively.238 Studies thathave compared the effect of estradiol COC on haemostatic variables to that of EE/LNG COC suggestthat use of estradiol-containing COC (particularly estradiol/nomegestrol acetate) is associated with a30

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haemostatic profile similar to or more favourable than that with EE/LNG COC. The potential impactof this on VTE risk remains to be clarified.5,239–243
10.1.4 Effect of route of administration on VTE risk
Data for VTE risk associated with the EE/norelgestromin CTP and EE/etonogestrel CVR are limited
and conflicting.
Combined transdermal patch
A systematic review244 identified conflicting evidence from seven observational studies
that compared the VTE risk associated with use of the CTP to that with use of COC
containing LNG or norgestimate. One retrospective cohort study245 and one case-control
study246 reported significant, 2-fold greater VTE risk among CTP users compared to
COC users. One cohort study247 considered only risk of cerebral venous thrombosis andrecorded very few events (two in COC users and none in CTP users). Of the remaining
four case-control studies, one248 reported a non-significantly increased VTE risk for CTP
users compared to COC users (OR 2.0; 95% CI 0.9–4.1) and three248–250 did not findsignificant differences.
Combined vaginal ring
A systematic review244 identified three studies that examined VTE among vaginal
ring users compared to EE/LNG COC users. Two studies (one cohort 105 and one
case-control250 study) did not find a statistically significant difference between CVR
and EE/LNG COC users. The third (cohort) study245 reported an increased risk of
VTE (RR 1.9; 95% CI 1.3–2.7) in women using the CVR compared to EE/LNG COC
users.
10.1.5 Women with inherited thrombophilias
Known thrombophilia is an absolute contraindication to CHC use (UKMEC 4).96

Evidencelevel 2-

Evidencelevel 2-

Evidencelevel 2+

Women with inherited thrombophilias who use CHC are at significantly greater risk of
VTE than CHC users without thrombophilia. A systematic review and meta-analysis251
which included data from 14 observational studies concluded that COC users with mild
thrombophilias (e.g. factor V Leiden heterozygosity and prothrombin G20210A mutation)
had a risk of VTE almost six times that of COC users without thrombophilia (RR 5.89;
95% CI 4.21–8.23); severe thrombophilias (e.g. antithrombin, protein C and protein S
deficiencies and the homozygous forms of factor V Leiden and prothrombin G20210A)
were associated with a more than 7-fold increase in VTE risk (RR 7.15; 95% CI 2.93–
17.45).
Cohort studies included in the systematic review reported absolute risks of VTE as highas 4.3 (95% CI 1.4–9.7) and 4.62 (95% CI 2.5–7.9) per 100 pill years among COC users
with antithrombin, protein C or protein S deficiency who also had a family member withboth a thrombophilia and a VTE event. The authors of the review conclude that comparedto the general CHC-using population (VTE risk of 6 per 10 000 woman-years), CHC users
with a mild thrombophilia and a family history of VTE have an 8- to 33-fold increase
in VTE risk; for CHC users with a severe thrombophilia and a positive family history,
VTE risk is increased 70-fold. It is suggested that there could be co-inheritance of otherthrombophilic defects.251

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Thrombophilia screening
Screening for inherited thrombophilia in women with no known family history ofthrombophilia is considered to be neither cost effective nor necessary.252,253 Screening
women with a first-degree relative who has a hereditary thrombophilia is of uncertain
benefit; studies evaluating the cost-effectiveness are of generally low quality.254 One
limitation of these studies is that they consider only 1 year of COC use rather than thelonger durations that reflect many women’s use. Furthermore, they do not take into
account other situations that increase VTE risk – pregnancy, surgery, air travel – forwhich knowing thrombophilia status could be beneficial.

Evidencelevel 2-

Due to the lack of high-quality evidence, the GDG advises that a woman with a first-degree relative
who has an inherited thrombophilia can be counselled that a negative thrombophilia screen does notnecessarily exclude thrombophilia (particularly if the relative has had a VTE event). A contraceptive
method other than CHC that is not associated with increased VTE risk should be considered.
10.2 Arterial thromboembolic disease
Key information

C

Current use of CHC is associated with a very small increased risk of myocardial
infarction (MI) and ischaemic stroke that appears to be greater with higher dosesof estrogen in COC.

Clinical recommendation

C

Women should be informed that current use of CHC is associated with an increased
risk of MI and ischaemic stroke but that that these events are still extremely
uncommon in CHC users.

✓

Use of CHC by women with significant additional risk factors for arterial disease
should be strongly cautioned or avoided.

The absolute risk of arterial thromboembolism (ATE) in young women is very low but increases
markedly with age through a woman’s reproductive years.255 Most studies indicate that current use of
CHC is associated with increased risk of ischaemic stroke and myocardial infarction (MI) compared to
non-use of CHC; risk appears to increase with increasing dose of estrogen in COC. The absolute riskof ATE remains extremely small for CHC users; a large Danish cohort study reported 2.1 thrombotic
strokes and 1.0 MI per 10 000 woman-years of use of hormonal contraception (the majority of thecohort used COC).255 However, any increase in risk is important because the morbidity and mortality
associated with ATE events are significant. The risk of ATE among past-users of COC is similar tothat for never-users.
FSRH UKMEC 201696 recommends that use of all CHC is either strongly cautioned or avoided for
women with hypertension, women over the age of 35 years who smoke, women with multiple risk
factors for cardiovascular disease including smoking, hypertension, high BMI, dyslipidaemias anddiabetes, and for women with migraine with aura or migraine without aura that is of new onset during
use of CHC.96 A family history of ATE events does not preclude use of CHC.
The evidence relating to risk of ATE and current use of CHC is summarised below. No RCTs are
identified. The observational studies included are limited by the fact that ATE events are rare among
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women of reproductive age, data are often extracted from databases or self-reported by participating
women, and data relating to bias and confounding factors are incomplete. Overall the evidence
suggests that risk of ATE associated with COC use increases with increasing EE dose. Risk ofischaemic stroke does not appear to vary according to progestogen type in COC; risk of MI does notvary clearly according to progestogen type in COC, although some studies suggest that risk could
be lower with third-generation progestogens than with first- or second-generation. Evidence relating
to ATE risk with use of the CTP, CVR and estradiol-containing COC is limited, but risk appears to be
similar to that associated with EE COC use.
10.2.1 CHC use and risk of myocardial infarction
A Cochrane Review256 of 24 observational studies found a significantly increased riskof MI for current users of COC compared with non-users (RR 1.6; 95% CI 1.2–2.1).
The review included studies of users of older COC with higher EE content. Threeearlier meta-analyses reported similar significant results (ORs 1.70 (95% CI 1.2–2.3),
1.84 (95% CI 1.38–2.44) and 2.48 (95% CI 1.91–3.22) for current use compared to
non-use).257–259 One further meta-analysis210 found a non-significant increased risk of
MI associated with current COC use (OR 1.34; 95% CI 0.87–2.08).
10.2.2 CHC use and risk of ischaemic stroke
A Cochrane Review256 found a RR for ischaemic stroke of 1.7 (95% CI 1.5–1.9)
for current COC use compared to non-use. This is consistent with the findings ofthree previous meta-analyses which reported OR for ischaemic stroke in current
COC users of 1.8 (95% CI 1.2–2.8),259 2.12 (95% CI 1.56–2.86)257 and 1.90
(95% CI 1.24–2.91)210 compared to non-users. A 2015 meta-analysis260 found a higher
OR (OR 2.47; 95% CI 2.04–2.99) for first-time ischaemic stroke with current COC use
compared with non-current use, however the risk declined significantly with decreasing
estrogen dose.
10.2.3 Estrogen dose and risk of ATE
A Cochrane Review256 and a meta-analysis260 concluded that risk of ATE seemed toincrease with higher doses of estrogen in COC.

Evidencelevel 2+

Evidencelevel 2+

Evidencelevel 2+

Myocardial infarction: A large cohort study255 (data extracted from Danish databases) – which
was included in the Cochrane Review – reported RR of MI of 1.4 (95% CI 1.07–1.81) for users of
COC containing 20 μg EE and 1.88 (95% CI 1.66–2.13) for users of COC containing 30–40 μg EE
compared to non-users. One meta-analysis258 of 19 case-control studies and four cohort studies
found a significantly increased risk of MI with preparations containing 30–49 µg EE (OR 1.97;
95%CI 1.43–2.71) but no increased risk for 20 µg EE preparations (OR 0.92; 95% CI 0.21 –4.08).
A later (2016) large French cohort study237 reported a significantly lower risk of MI with use of
COC containing 20 µg EE than with use of COC containing 30–40 µg EE (RR 0.74; 95% CI 0.67–0.82).
Ischaemic stroke: A meta-analysis260 found that the OR for ischaemic stroke was 1.56 (95% CI
1.36–1.79) in women using COC containing 20 μg EE, 1.75 (95% CI 1.61–1.89) for 30–40 μg EE
and 3.28 (95% CI 2.49–4.32) for ≥50 μg EE compared with non-current COC use. The Danish
cohort study reported a RR of ischaemic stroke of 1.60 (95% CI 1.37–1.86) for users of 20 μg
EE and 1.75 (95% CI 1.61–1.92) for users of EE 30–40 µg compared to non-users. The 2016
French cohort study237 reported a significantly lower risk of ischaemic stroke with use of a
COC containing 20 μg EE than with use of a COC containing 30–40 μg EE (RR 0.82; 95%
CI 0.70–0.96).
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10.2.4 Progestogen type and risk of ATE
A Cochrane Review256 concluded that risk of MI and ischaemic stroke did not vary
clearly according to progestogen type.

Evidencelevel 2+

Myocardial infarction: One meta-analysis259 found no significant association between progestogen
type and risk of MI. ADanish cohort study reported RR for MI of 1.33–2.28 for use of 30–40 µg EE COC
containingdifferentprogestogens(comparedwithnon-useof CHC), butthedifferencesinriskbetween
progestogens were not significant.255 Two meta-analyses reported OR for MI compared with CHC
non-use of 1.13 (95% CI 0.66–1.92)261 and 1.34 (95% CI 0.91–1.98)210 for use of third-generation
COC, while for second-generation COC the OR were 2.18 (95% CI 1.62–2.94)261 and 1.79 (95%
CI 1.16–2.75)210 and for first-generation COC, 3.37 (95% CI 2.04–5.54).210 One meta-analysis258
reported a significantly increased risk of MI for users of first- and second-generation COC
compared to non-users (OR 2.21; 95% CI 1.30–3.76; p=0.004) and 2.17 (95% CI 1.76–2.69;
p<0.0005), respectively), but not for users of third-generation COC (OR 1.27; 95% CI 0.96–1.67;
p=0.094).
Ischaemic stroke: Two systematic reviews257,259 reported similar risk of ischaemic stroke for current
users of second- and third-generation COC.
DRSP-containing COC: One large database cohort study found that women using COC containing
EE 30 µg and DRSP had an increased risk of ATE compared to women using preparations of COC
containing 20–35 µg EE and LNG, norethisterone or norgestimate but this risk was only statisticallysignificant in women aged 35–55 years.262 Conversely, data from the EURAS study224 suggested a
non-significant reduction in ATE risk with EE/DRSP compared to other COC, and the continuation ofthis study reported a significantly lower risk of ATE with EE/DRSP compared to other COC (adjusted
HR 0.4; 95% CI 0.2–0.8).263 An Israeli cohort study reported similar ATE risks for users of EE/DRSP
and second- and third-generation COC.264
10.2.5 Estrogen type and risk of ATE
The limited data relating to risk of ATE associated with use of COC containing estradiol suggest thatrisk is similar to that associated with EE COC.238
10.2.6 Route of administration and risk of ATE
A recent systematic review244 identified one cohort study265 and one case-control study246 Evidence
that compared ATE risk for use of the CTP with that of COC containing norgestimate; level 2neither study reported a significant difference in risk of MI or ischaemic stroke. Twoprospective cohort studies were not included in the systematic review because thecomparator group comprised users of multiple different COC; one reported similar riskof ATE for use of the CVR to that for use of (various) COC.263 The other study262 foundno significant differences in ATE risk between users of the CTP, CVR and (various)
COC.
10.2.7 Additional risk factors for ATE
Risk of ATE is greater for COC users with additional risk factors such as hypertension266 andsmoking96 and may be increased by hyperlipidaemia.267

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Migraine and risk of ischaemic stroke
The evidence (summarised below) suggests that CHC users with migraine with aura are at greaterrisk of ischaemic stroke than CHC users without migraine. UKMEC 201696 recommends that use of
CHC by women who have migraine with aura is UKMEC 4. For women who have migraine withoutaura, initiation of CHC is UKMEC 2, but if there is new-onset migraine after starting CHC, the risksof continuation generally outweigh the benefits (UKMEC 3).
It is important to note that although relative risk of ischaemic stroke is increased, the number ofischaemic strokes in women of reproductive age is small and the absolute risk remains low. Using
data from the UK General Practice Research Database the incidence of ischaemic stroke in all
women aged 15–49 years was estimated at 3.56 (95% CI 3.05–4.07) per 100 000 per year.268
Meta-analysis of evidence from observational studies indicates that the risk of ischaemic
stroke in individuals who have migraine is approximately twice that of those who do not havemigraine.269–273 Four meta-analyses269,270,272,273 find a significant association between migrainewith aura and ischaemic stroke, but only one 272 reports a significant association for migraine
without aura. Use of CHC independently increases the risk of ischaemic stroke (see Section
10.2.2).
Evidence is limited regarding risk of ischaemic stroke amongst women who have migraine and are also
users of CHC.270,274,275 A 2016 systematic review274 concluded that the fair to poor quality evidence
identified suggests an increased risk of stroke amongst CHC users with migraine compared with
non-users of CHC who have migraine, and that the effect on ischaemic stroke risk of migraine and
CHC are additive. A recent nested case-control study276 which considered data from US databases
identified 25 887 ischaemic strokes amongst women aged 15–49 years between 2006 and 2012.
Compared to women who did not have migraine and did not use CHC, the OR for ischaemic stroke
was 1.8 (95% CI 1.1–2.9) for women with migraine without aura who also used CHC. This is similar
to the OR observed for women with migraine without aura who did not use CHC (OR 2.2; 95% CI
1.9–2.7); CHC was not observed to further increase risk. For women who had migraine with aura,
the OR for ischaemic stroke was 2.7 (95% CI 1.9–3.7) with no CHC use and increased to 6.1 (95%
CI 3.1–12.1) if they also used CHC compared to women without migraine or CHC use.
10.3 CHC use and risk of haemorrhagic stroke
Two meta-analyses of data from observational studies report no significant increase inrisk of haemorrhagic stroke among COC users (OR for current use of COC compared
to non-use of COC 1.1 (95% CI 0.7–1.9)259 and 1.03 (95% CI 0.7–1.49)).210

Evidencelevel 2+10.4 Breast cancer
Clinical recommendation

C

Women should be advised that current use of CHC is associated with a small
increased risk of breast cancer which reduces with time after stopping CHC.

10.4.1 CHC use and risk of breast cancer
Current CHC use

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FSRH guideline: CHC

A recent large Danish cohort study reported a relative risk of breast cancer of 1.19
(95% CI 1.13–1.26) for current or recent users of COC compared to never-users ofhormonal contraception.277 Risk appeared to increase with duration of use. No majordifferences in risk were observed between COC containing different progestogens. The
study adjusted for potential confounding factors, but data for alcohol intake, age at
menarche and breastfeeding were not available and those for BMI were incomplete.

Evidencelevel 2+

Meta-analyses of data from observational studies, 278,279 sometimes including use ofolder COC with higher estrogen content, have reported a slight but significant increased
risk of breast cancer among women currently using COC compared with women who
have never used CHC, the RR ranging from 1.19–1.24. One meta-analysis of five cohort
studies found a very small but significant increase in breast cancer risk for every 5 years(RR 1.07; 95% CI 1.03–1.11) and 10 years (RR 1.14; 95% CI 1.05–1.23) of use; however,many of the individual studies did not have statistically significant findings. 280 Three
more recent studies, including the Oxford-Family Planning Association contraceptive
study and a meta-analysis of 44 observational studies, found no link between durationof COC use and breast cancer risk.196,281,282
Past CHC use
Increased breast cancer risk associated with current COC use has been found to
decline gradually after cessation of COC, with no significant increased risk of breast
cancer after 10 years of non-use.196,278,283,284 Compared with never-use of CHC,
reported RRs for breast cancer for ever-users of COC are close to unity (range 1.0–1.08) and non-significant.196,278,280,281,283,284 Very long-term follow-up of the RCGP Oral
Contraception Study cohort indicates that the increased breast cancer risk that is seenin current and recent OC users appears to be lost within approximately 5 years of
stopping, with no evidence of increased risk in later life.195 The evidence is that there isno significant association between use of COC and mortality from breast cancer.208,285–287
10.4.2 Family history of breast cancer
Women with a family history of breast cancer have an increased background risk ofbreast cancer compared to women with no such family history. 288 Several studies do,
however, suggest that women with a family history of breast cancer who have ever used
CHC are at no higher risk of breast cancer than women with a family history who havenever used CHC.204,278,289,290 UKMEC does not restrict use of CHC for women with afamily history of breast cancer.96
10.4.3 Genetic mutations relevant to breast cancer risk
UKMEC states that for carriers of known gene mutations associated with breast cancer(e.g. BRCA mutations) the risks of using CHC generally outweigh the advantages. 96
Women with such inherited mutations have a higher background risk for breast
cancer.291–294 The evidence regarding whether CHC use further increases the risk ofcancer for these women is inconsistent, with some systematic reviews/meta-analyses
reporting conflicting findings among the studies considered 295–297 and others finding no
increased risk with CHC use.202–204

Evidencelevel 2+

Evidencelevel 2-

Evidencelevel 2+Three meta-analyses202–204 based on observational studies conclude that carriers of
BRCA mutations who use COC have a reduced risk of ovarian cancer compared withnever-users (RR 0.50, OR 0.57 and OR 0.58). This advantage would need to be weighedagainst the potential increased risk of breast cancer.
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10.5 Cervical cancer
Clinical recommendation

C

Women should be advised that current use of CHC for more than 5 years is
associated with a small increased risk of cervical cancer; risk reduces overtime after stopping CHC and is no longer increased by about 10 years after
stopping.

Collaborative analysis298 of data from 24 worldwide observational studies, including
large UK cohort studies, suggested that current use of COC for more than 5 years
approximately doubled the risk of invasive cervical cancer (RR 1·90; 95% CI 1·69–2·13)
compared with never-use of COC. The risk declined after stopping COC, becoming thesame as that for never-users about 10 years after cessation. The analysis reported nosignificant increase in risk of invasive cervical cancer associated with use of COC forless than 5 years.

Evidencelevel 2+

Studies have consistently reported increased cervical cancer risk associated withcurrent use of COC that increases with duration of use and decreases with time after
cessation.283,299–301 Very long-term follow up of the RCGP Oral Contraception Study
cohort indicates that the increased cervical cancer risk that is seen in current and recent
OC users appears to be lost within approximately 5 years of stopping, with no evidence
of increased risk in later life.195 Few studies consider the risk of cervical cancer among
COC users who are human papillomavirus (HPV) positive.196
There is currently no evidence regarding whether the CVR, with its intravaginal administration, or the
CTP are associated with different cervical cancer risk than COC. Women should be informed about
the association between HPV and cervical cancer and given advice regarding condom use, smoking
cessation, regular cervical screening and, where appropriate, HPV vaccination. See WHO Guideline
Comprehensive Cervical Cancer Control: A Guide to Essential Practice.302

11. Side effects associated with CHC use
Some women using CHC report headaches, nausea, dizziness and breast tenderness. Different CHC
preparations and modes of administration can prove more or less tolerable to individual women. It is
important to note that there may be confounding factors contributing to women’s experience of side
effects; RCTs have found that women report side effects at similar rates in treatment and placebogroups.303
As many CHC side effects arise during the HFI rather than during active pill use, shortened HFI or
extended/continuous regimens may be helpful.3 Two systematic reviews27,28 reported that women
who use extended CHC regimens benefit from greater improvement of menstrual symptoms
associated with the HFI, including headaches, genital irritation, tiredness, bloating and menstrual
pain compared to women who use CHC cyclically (see Section 6.2.5).
Women who develop side effects which they find unacceptable can be advised to consider a different
formulation or mode of administration of CHC or a different contraceptive method which could havea more acceptable side effect profile.

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11.1 CHC and headache
See Section 10.2.7 regarding use of CHC by women with migraine.
Headache is common among women of reproductive age, whether or not they use contraception.
Headache is frequently reported as a side effect of CHC (often associated with the HFI) and issometimes cited as a reason for CHC discontinuation, but in studies headache also occurs withplacebo. Among women who have headache prior to CHC use, some women report worsening ofheadache after starting CHC while others report no change or improvement. Where an increasein headache is seen in the early cycles of CHC use this does not appear to persist with continued
use.304,305
Studies investigating the effect of CHC use on headache are of overall poor quality, limited by alack of information regarding which women had pre-existing headaches, absence of placebo arm or
non-CHC using controls. Relevant studies consider different CHC preparations taken for different
durations, with different comparators; some studies include migraine under the definition of headache
where others do not. As a result, comparison and interpretation of data is difficult.
A 2005 systematic review304 and a 2013 comprehensive literature review305 found no consistentassociation between CHC use and headache, regardless of progestogen type and route of CHC
administration. Lower estrogen doses do not appear to be associated with fewer headaches.
Extended or continuous CHC regimens reduce the frequency of headaches associated with the
HFI.
11.2 Unscheduled bleeding with CHC (breakthrough bleeding)
Unscheduled bleeding is a relatively common side effect of CHC. The incidence,
regardless of route of administration, is around 10–18% per cycle.306–309 This is notvery different from the background incidence of intermenstrual bleeding reported
among a UK population. In a postal questionnaire survey of 2438 women, some ofthem using contraception (including CHC), over the course of 1 year self-reported
cumulative incidence of intermenstrual bleeding was 17% (95% CI 14–19).310 HCPs
should be aware of other causes of unscheduled bleeding such as missed pills, sexuallytransmitted infections, pregnancy and cervical pathology.
Some studies suggest that the incidence of unscheduled bleeding decreases with time.
It is possible that women who find unscheduled bleeding unacceptable discontinue
their method of contraception and so over the course of a trial bleeding patterns seemto improve. In some studies with small drop-out rates the improvement over time isconvincing311 but in others the fall in incidence is in line with the decrease in the sample
size as women discontinue participation in the study. 309 Most studies do show thatunscheduled bleeding is more likely in the first cycle, and some show an improvement
over the first 3 months, with the incidence of unscheduled bleeding remaining constantfrom 4–12 months for both OC and the vaginal ring. 311 It makes sense to recommendthat women experiencing unscheduled bleeding continue their method for at least
3 months before seeking advice.312

Evidencelevel 1-

Evidencelevel 1-11.2.1 Differences in bleeding pattern between routes of CHC administration
The nearly constant rate of release of contraceptive steroids administered transdermally ortransvaginally, together with the theoretical advantages in respect of compliance, suggest that cycle
control could be better than that with COC.313
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OC versus CTP: A 2013 Cochrane Review99 identified four RCTs which compared cycle
control among women using the EE/norgestimate patch to that among women using avariety of COC. None showed any differences in cycle control despite compliance being
significantly better among patch users than among women using the COC in all threestudies reporting compliance. More recently published studies have explored different
formulations of patches, none as yet licensed.

Evidencelevel 2-

OC versus CVR: In the 2013 Cochrane Review99 seven trials with the CVR reported
bleeding data. Significant differences were found in four trials, all tending towards alower incidence of breakthrough bleeding (at least in some cycles) among CVR users
than among women using a variety of COC. One Chinese study published since theCochrane Review311 compared the CVR with COC containing 30 µg EE/3mg DRSP. The
authors reported significantly less bleeding/spotting in the CVR group than in the COC
group for all 13 cycles (p<0.05) These differences are biologically plausible since there
is greater bioavailability of steroids when administered through the vagina than throughother routes.313

Evidencelevel 2-11.2.2 Differences in bleeding patterns between formulations of oral contraceptives
Many studies have attempted to show differences in bleeding patterns between different Evidence
formulations of COC, however seldom do these studies compare like with like. For level 1example, COC containing different progestogens are compared but they often also
contain different doses of EE;314 monophasic formulations are compared with triphasic
formulations;314 and regimens with 7 days of placebo pills are compared with a regimen
with only two 2 days of placebo.308 The majority of such studies are undertaken bypharmaceutical companies as Phase 3 trials leading to licensing of a new product. The
comparator pill could be chosen to maximise the chance of the new product showing
non-inferiority. Moreover while the differences in the duration of unscheduled bleeding
may be statistically significant, the effect is often small and unlikely to influence
acceptability of the method; a difference between 12 and 15 days of unscheduled
bleeding over 90 days may not be clinically significant. 308
The evidence for an effect of the dose of estrogen on the incidence of unscheduled
bleeding is more persuasive than that for an effect of different types of progestogen.
Effect of estrogen dose: A 2013 Cochrane Review315 of 22 RCTs concluded that Evidence
women using 20 µg of EE experienced higher rates of unscheduled bleeding than level 1+
women using >20 µg. One study merits specific mention. Although criticised in thereview for not specifying who was blinded, Akerlund et al (1993)316 undertook an RCT
comparing women using a COC containing 150 µg desogestrel with either 20 µg or
30 µg EE. Thus the progestogen component was the same in both groups. Womentaking 20 µg EE were more likely to report irregular bleeding (OR 1.56; 95% CI 1.10–
2.20). The difference between the incidence of unscheduled bleeding was statisticallysignificant for 8 of the 12 months of follow-up.
Effect of progestogen type: A 2004 systematic review317 of 22 studies included two
RCTs that reported less unscheduled bleeding with third- compared with secondgeneration progestogens (RR 0.71; 95% CI 0.55–0.91). These RCTs were limited byshort study periods. Six RCTs found that cycle control was better with COC containing
second-generation versus first-generation progestogens, both for monophasic(RR 0.69; 95% CI 0.52–0.91) and triphasic formulations (RR 0.61; 95% CI 0.43–0.85).
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Effect of estrogen type: A number of studies have attempted to compare bleeding Evidence
patterns among women using COC containing natural estrogens as opposed to those level 1containing EE. Once again the type of progestogen is also different between theformulations, making the results difficult to interpret. Two RCTs comparing use of 1.5 mg
17β-estradiol/2.5 mg nomegestrol acetate30 and 30 µg EE/3 mg DRSP found that theincidence of unscheduled bleeding was comparable between the two formulations.318,319
One RCT comparing estradiol valerate/dienogest32 with 20 µg EE/100 µg LNG over sevencycles also found no difference in the proportion of women experiencing unscheduled
bleeding, but reported that women in the estradiol group experienced fewer bleeding/spotting days (median 16 vs 21 during Days 1–90; 12 vs 15 during Days 91–180;
p<0.0001).308
11.2.3 Differences in bleeding patterns between CHC regimens
See Section 6.2.4.
Unscheduled bleeding with CHC: summary
In summary, HCPs should inform women that unscheduled bleeding commonly occurs with
CHC use but is likely to improve over the first 3–4 months of use. Formulations with higher
doses of EE are probably associated with a lower risk of unscheduled bleeding when used ina traditional regimen, and pills containing second-generation progestogens could offer better
cycle control than those containing norethisterone. Blood levels of exogenous hormones
may vary 10-fold between individuals320 and intra-individual differences also occur, so whatworks for one woman may not work for another. Trial and error may therefore be the best
approach for an individual woman to find a formulation that suits her needs. Extended orcontinuous regimens could offer less unscheduled bleeding. HCPs should consider othercauses of unscheduled bleeding. For guidance on the management of unscheduled bleeding
in women using hormonal contraception, refer to the FSRH Guideline Problematic Bleedingwith Hormonal Contraception.312
11.3 Mood
Mood change is a common complaint among CHC users 321 but a relatively infrequentreason for discontinuation.322 Numerous studies have tried to assess the magnitude ofthe effect of CHC on mood. A recent systematic review323 concluded that meta-analysis
is not possible due to the wide heterogeneity between the studies which compare
different types and formulations of hormonal contraceptives in the same cohort and use
different instruments for assessing mood change. Other complicating factors include
the well documented benefits for many women of CHC for PMS (see Section 9.3),
menstrual pain (see Section 9.2) and vaginal bleeding patterns (see Section 11.2), allof which could themselves affect mood.

Evidencelevel 2-

Few studies have compared healthy CHC users (not complaining of PMS or menstrual Evidencepain) with women not using hormonal contraception and even fewer are RCTs. One RCT level 1among women who were sterilised or whose partners were sterilised taking a COC, POPor placebo found no difference in depressive symptoms by the third month of treatment.324
A recent large, double-blind RCT325 randomised 340 women in Sweden to a standard
30 µg EE/LNG COC or placebo taken for 21 days with a 7-day pill-free interval for threecycles.

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Pregnancy was prevented with condoms. Scores using standardised instruments
before treatment and at the end of 3 months showed a ‘modest’ decrease in general
well-being among women using the COC but no differences in depressive symptoms.
The predictable withdrawal bleed during the HFI could have prompted some women to
guess that they were taking the COC, and in one survey of women who were asked
about anticipated side effects before starting COC 20% said they expected to have moodchanges.326

Evidencelevel 1-

Most observational studies are reassuring. Four large epidemiological studies using
standardised depression screening instruments among women using modern hormonal
contraceptives undertaken in Australia,327 Finland328,329 and the USA330 showed noincrease in the incidence of depression associated with CHC use. However a recently
published Danish nationwide prospective cohort study reported a significant association
between CHC use and depression. The study followed over 1.06 million women aged
15–34 years with no prior diagnosis of depression.331 Compared with non-users, current
users of COC had a RR of first use of an antidepressant of 1.23 (95% CI 1.22–1.25),
users of a CTP (RR 2.0; 95% CI 1.76–2.18) and users of a CVR (etonogestrel) (RR 1.6;
95% CI 1.55–1.69). The RR of first use of an anti-depressant was also increased among
women using POP or LNG-IUS. Similar or slightly lower estimates were found for RR offirst diagnosis of depression. Risk generally decreased with increasing age; adolescents(age range 15–19 years) using COC had a RR of a first use of an antidepressant of
1.8 (95% CI 1.75–1.84) and those using POPs (RR 2.2; 95% CI 1.99–2.52). However,significant confounding factors cannot be excluded and a causative association is notestablished.

Evidencelevel 1-The same authors found associations between ever-use of CHC and increased riskof first suicide attempt, and between ever-use of OC and increased risk of suicidecompared with never-users of hormonal contraceptives.332 Risk did not differ significantly
by COC formulation. Potential confounding factors including psychiatric diagnoses
and antidepressant use were considered. Of previous cohort studies, one 285 reported
a positive association and four208,333–335 found no association between OC use andsuicide.
While some studies have suggested differences in the incidence of mood change
between COC formulations (EE dose316, progestogen type336) no consistent trends
have been reported. It is possible that formulations containing an anti -androgenic
progestogen such as drospirenone337,338 could have a more beneficial effect on moodthan preparations containing other progestogens. Continuous use of CHC may be of
benefit to mood.162 Data on the effects of the CVR or CTP are insufficient to allow any
conclusions on their relative effects on mood.99

Evidencelevel 1-

Effect of CHC on mood: summary
The evidence suggests that some women may experience negative mood changes when taking
CHC. However there is not clear, consistent evidence that CHC use causes depression; moodchange is common and often related to external events. The GDG recommends that if a woman
who experiences negative mood changes wishes to continue using CHC, a different formulation
containing an alternative progestogen could be tried empirically. If the negative mood change ispremenstrual, continuous use of CHC may be of benefit.

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11.4 Weight gain
There is no clear evidence that use of CHC causes weight gain. A 2014 Cochrane
Review339 of 49 RCTs identified only four trials that compared CHC with placebo orwith no intervention; the remainder compared different CHC formulations. The limited
evidence does not support a causal association between use of CHC and weight
gain, and there is no consistent evidence that different CHC formulations affect weight
differently. A systematic review175 which identified data for women aged under 18 years
from nine observational trials, concluded that there is no evidence of an association
between CHC use and weight gain in this group of women.

Evidencelevel 1+

11.5 Effect on libido
Libido is influenced by many social and psychological factors as well as age, health and medications.
The available evidence regarding the potential effect of CHC on libido is mixed and is limited byuse in different studies of different CHC preparations and assessment tools, and by lack of placebo
control or a non-hormonal comparator group in many studies. Overall there is no clear evidence ofan association between use of COC containing ≥20 µg EE and libido.
A 2013 systematic review340 included data for 8422 women using various CHC from36 trials (five RCTs, the remainder observational studies). The review found no clear
effect of CHC on libido. Despite the fact that active testosterone levels (where measured)
were reduced during CHC use, COC users reported an increase in sexual desire in
15 studies and no impact on sexual desire in 12 studies. Decreased sexual desire wasreported in nine studies. The identified evidence suggested that libido could be lower
among women using COC containing <20 µg EE than in users of COC with ≥20 µg EE.
A short subsequent trial341 which randomised 80 women to use either EE/DRSP COC
or barrier/fertility awareness method (FAM) for 3 months reported lower Female Sexual
Function Index (FSFI), desire and arousal scores for COC users.

Evidencelevel 1+

11.6 Return to fertility
There is no evidence that use of COC is associated with subsequent long-term reduction in fertility.
Studies reporting return of ovulation after use of COC indicate that the majority ofwomen ovulate within about a month of COC cessation whether they have used cyclicalor extended COC regimens.74,342,343 Of 187 women stopping a 20 µg EE/LNG COC afterat least 6 months of use in a cohort study, 98.9% returned to spontaneous menstruation(or became pregnant) within 90 days.73

Evidencelevel 2-The evidence from observational studies indicates that among women planning toconceive, pregnancy rates are high in the 2 years after stopping standard cyclical or
extended regimen COC.344–346 A systematic review346 which included three prospective
observational studies reported typical 1-year pregnancy rates following cessationof OCs ranging from 79.4% to 95.0%. Median time to pregnancy was 2.5–3 cycles.
Cohort studies with a non-COC comparator group suggest that compared to women
discontinuing barrier methods or who had not been using contraception, those stopping
COC and planning to conceive experience a transient delay in conception over the firstfew months but that by 1–2 years pregnancy rates are comparable.347–352
There is no evidence that increasing duration of COC use is associated with reduced
fertility. Some observational studies have in fact suggested that longer duration of COC
use could be associated with greater fecundity than short-term use.351,353–355
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12. What should be done in an initial CHC consultation?
Box 2 (which links to relevant sections) summarises the suggested content of an initial consultation witha woman who requests CHC. The consultation should focus on provision of safe, effective contraceptionthat suits a woman’s requirements and that could also provide non-contraceptive benefits. Such a
consultation is, however, an important opportunity to assess whether a woman is already at risk ofpregnancy and could require emergency contraception or pregnancy testing, to assess STI risk and offer
advice and testing, and to remind women about the importance of cervical screening.
Box 2: Suggested content of an initial combined hormonal contraception consultation (links
to subsequent sections)
Assessingsuitabilityof CHC for
individual
woman

►
►
►
►

Assessment of medical eligibility
Assessment of medical history and lifestyle factors (UKMEC)
Measurements and tests – blood pressure and body mass index (BMI)
should be documented
Assessment of factors that could affect contraceptive effectiveness↓ If eligible

Choosing CHC
or an alternative
method↓ If ineligible

Discuss:► Effectiveness, factors that
affect effectiveness► Non-contraceptive benefits► Health risks & Specific advice► Side effects►►

Explain why CHC is not suitable
Offer alternative methods that the
woman is medically eligible to use↓

Choosing type of
CHC

Discuss/offer appropriate alternative
methods (including LARC)↓
Combined oral contraception
(COC)

↓
→

Woman chooses alternative method↓

Combinedtransdermal patch(CTP)

Combined vaginal
ring (CVR)

Only oneavailable in UK
Norelgestromin/
Ethinylestradiol

Only one available in UK
Etonogestrel/
Ethinylestradiol(Nuvaring® ,SyreniRing®)►

Consider ≤30 µg EE COC with
LNG or NET first line
Consider health risk/potential
benefits associated with different
formulations

Choosing
regimen for CHC
use►

Discuss both standard and tailored regimens

Duration of CHC
prescription►

Up to 1 year
Note that only 3 months’ supply of NuvaRing® can be dispensed at any one time

Choosing CHC
formulation►►↓
Provide other essential information
CHC, combined hormonal contraception; COC, combined oral contraception; EE, ethinylestradiol; LARC, long-acting
reversible contraception; LNG, levonorgestrel; NET, norethisterone; UKMEC, United Kingdom Medical Eligibilty Criteria.

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12.1 Assessment of suitability of CHC for an individual woman
Key informationC

Use of suitable self-completed checklists for medical eligibility appears to beaccurate and acceptable to women.

Clinical recommendation✓

Assessment of medical eligibility for CHC should include medical conditions,
lifestyle factors and family medical history.
A drug history should identify:-✓►►

any prescribed or non-prescribed drug that could affect the effectiveness of thecontraceptive
any prescribed or non-prescribed drug that could itself be affected by thecontraceptiveC

A recent, accurate blood pressure recording should be documented for all womenprior to first CHC prescription.

D

BMI should be documented for all women prior to CHC prescription.

D

Pelvic examination is not required prior to initiation of CHC.

D

Breast examination, cervical screening, testing for thrombophilia, hyperlipidaemia
or diabetes mellitus and liver function tests are not routinely required prior toinitiation of CHC.

✓

Women for whom CHC is unsuitable should be offered alternative effective
contraception.

The HCP should obtain a history that includes the woman’s age, past and current medical conditions,smoking, drug history (prescription, non-prescription and herbal preparations) and family history ofsignificant medical conditions. BMI and blood pressure should be recorded.
12.1.1 Assessment of medical eligibility for CHC
Medical history and lifestyle factors
Medical eligibility must be assessed prior to prescription of any contraceptive method including
CHC. The UK Medical Eligibility Criteria for Contraceptive Use 2016 (UKMEC 2016)96 provides
recommendations for the safe use of CHC by women with different personal characteristics andmedical conditions. Each of the personal characteristics or medical conditions considered by the
UKMEC is assigned to one of four categories as defined in Table 6. UKMEC 3 and UKMEC 4characteristics and conditions for CHC use are listed in Appendix 2. If a woman has multiple
conditions that are UKMEC 2 for CHC use and relate to the same risk, the suitability of CHC should
be carefully considered.

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Table 6: Definition of categories for the UK Medical Eligibility Criteria for Contraceptive Use(UKMEC)96
UKMEC

Definition of category

Category 1

A condition for which there is no restriction for the use of the method.

Category 2

A condition where the advantages of using the method generally outweigh the theoreticalor proven risks.

Category 3

A condition where the theoretical or proven risks usually outweigh the advantages of using
the method. The provision of a method requires expert clinical judgement and/or referral toa specialist contraceptive provider, since use of the method is not usually recommended
unless other more appropriate methods are not available or not acceptable.

Category 4

A condition which represents an unacceptable health risk if the method is used.

Specific attention should be given to enquiring about:► Thrombophilia or previous VTE► Ischaemic heart disease, stroke or transient ischaemic attack, peripheral vascular disease► Additional risk factors for venous or arterial thromboembolism (e.g. smoking, obesity, recent
childbirth, immobility, hypertension, migraine, diabetes, hyperlipidaemia, antiphospholipid
antibodies, arrhythmia, complicated congenital/valvular heart disease or cardiomyopathy)► Personal history of breast cancer/known breast cancer-related gene mutation► Hepatobiliary disease► Recent childbirth, current breastfeeding.
Use of a self-completed checklist to assess medical eligibility for CHC
The use of a suitable self-completed checklist may be appropriate for identifying
personal characteristics, medical conditions or use of medication that could affectmedical eligibility for CHC. Four studies (two from the USA356,357 and one each from theUK358 and Tanzania359) which examined assessment of medical eligibility for CHC using
questionnaires self-completed by women compared to clinical assessment by trained
providers reported high levels of agreement between women and HCPs. All four studies
found that women were more likely than providers to identify contraindications. The UK
study concluded that no clinically important information relevant to a particular woman’s
use of CHC was missed and none of the women would have been wrongly prescribed
CHC based only on their self-completed questionnaires.

Evidencelevel 2-

If self-assessment checklists are used they should be developed and validated toensure that they are effective.
Measurements and tests
Blood pressure and body mass index (BMI) should be documented for all women before prescriptionof CHC. The prescriber must be confident that measurements are recent and accurate.
Blood pressure: Women with severe hypertension (systolic pressure ≥160 mmHg or Evidence
diastolic pressure ≥100 mmHg) should not use CHC (UKMEC 4). Women with less severe level 2hypertension (systolic pressure 140–159 mmHg or diastolic pressure 90–99 mmHg),
or with adequately controlled hypertension should not use CHC (UKMEC 3). Bloodpressure should therefore be evaluated before initiating CHC.

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Evidence from a systematic review360 suggests that risk of MI and ischaemic stroke is higher
among women who do not have their blood pressure measured before initiating COC.

Evidencelevel 2-

Women with raised blood pressure measured in non-primary care settings (e.g. at a pharmacy or
specialist services) should be provided with suitable alternative effective contraception and advised
to see their general practitioner for blood pressure assessment.
Weight (BMI): Women with BMI <35 kg/m2 generally can use CHC (UKMEC 2). Women with BMI≥35 kg/m2 generally should not use CHC (UKMEC 3), although CHC may be prescribed by a specialist
provider. BMI should be documented before starting CHC. Baseline weight could additionally be
helpful for monitoring any changes and counselling women who might be concerned about later
weight change perceived to be associated with their contraceptive method.
Pelvic examination: A consultation regarding contraception may be used as an opportunity for
health screening but screening should not be a condition for prescribing. Pelvic examination is notnecessary before initiation of CHC because it does not affect the decision to prescribe or withhold
hormonal contraception.361
Clinical breast examination: Although women with current breast cancer should not use CHC(UKMEC 4), screening asymptomatic women with a clinical breast examination before initiating CHC
is not necessary because of the low prevalence of breast cancer among women of reproductive age.
A systematic review361 did not identify any evidence regarding outcomes among women who werescreened versus not screened with a breast examination before initiation of hormonal contraceptives.
Breast self-examination can be encouraged.
Laboratory testing: A systematic review362 conducted to evaluate the evidence regarding healthoutcomes among women with and without laboratory testing to identify certain medical conditions,
including diabetes, hyperlipidaemia, liver disease, cervical cancer, STIs or human immunodeficiency
virus (HIV), prior to initiating contraceptives did not identify any relevant evidence.
The GDG (in line with the WHO Selected Practice Recommendations forContraceptive) advise that routine screening and examination other than bloodpressure and BMI are unnecessary prior to prescription of CHC and do not contribute
substantially to the safe and effective use of CHC.

Evidencelevel 412.1.2 Assessment of factors that could affect contraceptive effectivenessDrug interactions
Some medications could reduce the contraceptive effectiveness of CHC by induction of hepatic
enzymes. Contraceptive hormones can affect the action of certain medications. Refer to the FSRH
Guideline Drug Interactions with Hormonal Contraception 118 for further information. (See also
Section 7.2.3).
Malabsorption
The effectiveness of COC (but not the CTP or CVR) could be reduced by malabsorption resulting
from, for example, vomiting and severe diarrhoea (see Section 7.2.4), bariatric surgery, small bowel
resection (see Section 7.2.2) or inflammatory bowel disease (see FSRH Guideline Sexual andReproductive Health for Individuals with Inflammatory Bowel Disease).363

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12.1.3 Women for whom CHC is unsuitable
Women assessed as medically ineligible for CHC should be told why, and the risk to their health should
be explained. Alternative contraceptive methods which can be safely used should be discussed andoffered.
Women with medical conditions or using medications that could reduce contraceptive effectivenessshould be given advice regarding (and where possible provided with) alternative methods that would
be effective for them.
12.2 Choosing a method of contraception
Women requesting CHC who are assessed as medically eligible should be provided with the following
information about CHC to enable them to make an informed decision as to whether the method issuitable for them:►►►►

Effectiveness and factors that can affect effectiveness (see Section 7)
Non-contraceptive benefits (see Section 9)
Health risks (see Section 10)
Side effects (see Section 11)

Women should also be offered information about, and be given the opportunity to discuss, othersuitable contraceptive methods. However, care should be taken to ensure that women do not feel
coerced into choosing any particular method. For further information about alternative methods
refer to the other method-specific FSRH Guidelines and to UKMEC 2016, available on the FSRH
website.
12.3 Choosing type and formulation of CHC
Key information✓

COC containing ≤30 µg EE in combination with levonorgestrel or norethisterone isa reasonable first-line choice of CHC to minimise cardiovascular risk.

Women should be informed that CHC is available as COC, CTP and CVR and that different
formulations of COC are available. When supporting women to make an initial choice of CHC,
providers should explain that some types of CHC are associated with a lower risk of cardiovascular
events than others; it should, however, be made clear that differences in the numbers of such events
are small. It may be useful for a woman to know that there is no clear evidence that there are fewer
problematic side effects (as opposed to risks) with any particular CHC. However if side effects areexperienced with one formulation another could be more suitable.
The GDG recommends that a COC containing ≤30 μg EE in combination with levonorgestrel or
norethisterone is a reasonable first-line choice of CHC to minimise cardiovascular risk.
12.4 Choosing a regimen for CHC use
Women should be provided with information regarding both standard and tailored CHC regimens (seeSection 6). CHC providers should assess women’s preferences regarding frequency of scheduled
bleeding and associated withdrawal symptoms to support women in making informed choices about
the CHC regimen that best meets their needs.
Key messages that may be useful when discussing extended or continuous regimens are included
in Box 3.

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Box 3: Key messages for women considering use of tailored combined hormonal contraception
regimens
The evidence from studies is that combined hormonal contraception (CHC) is as safe and at
least as effective for contraception if it is taken as an extended or continuous regimen as it iswhen it is taken in a traditional 21/7 cycle.
► A woman who is using CHC does not need to have a monthly withdrawal bleed to be healthy.
► There is no build-up of menstrual blood inside a woman who uses CHC for an extended time
without a break; extended CHC use keeps the lining of the womb thin.
► Withdrawal bleeds during cyclical use of CHC have been reported by women who are pregnant;women should not consider monthly bleeds on CHC to be reassurance that they are not pregnant.
► By using extended or continuous CHC the frequency of withdrawal bleeds and associated symptoms(e.g. headache, mood change) is reduced; this could be useful for women who have heavy or
painful bleeding or problematic symptoms associated with the hormone-free interval (HFI).
► The ovaries start to become active during the traditional 7-day HFI. Fewer and/or shorter breaks
in CHC use could mean that the risk of pregnancy could theoretically be lower with extended
or continuous regimens than if a 7-day break is taken every month.
► There can be irregular bleeding or spotting in the first few months of CHC use, particularly withextended or continuous regimens; this does not usually mean that there is any medical problem
and it generally improves with time.
► The evidence from studies is that using extended or continuous regimens of CHC does notaffect the return of a woman’s fertility when she stops CHC.
►

12.5 Other important supporting information
Clinical recommendation✓

Women should be provided with written information or a link to a trusted online
resource to support safe, effective CHC use.

It is important that women are offered the opportunity to ask questions. Women should be provided
with the following information regarding use of their chosen CHC:
►

►

►

►
►

►

►

►

When/how to start the method (see Section 6.3), highlighting whether additional contraceptive
precaution is required before the contraceptive effect of CHC can be relied upon
What to do when the method is used incorrectly or inconsistently (see Section 8) and when
emergency contraception may be indicatedHealth risks associated with use of CHC (see Section 10) and specific advice for travel, living ataltitude and having surgery (see Section 14)
Key signs and symptoms that should alert them to seek medical advice (see Box 4)
Significant new health events that should prompt them to review their contraceptive method (seeBox 4)
Advice that they should check with the prescriber of any new medication or with their contraceptive
provider whether any new prescribed or non-prescribed drug could affect the contraceptive
effectiveness of CHC
Arrangements for subsequent prescription of CHC (including obtaining an emergency supply)and follow-up (see Section 13)
What to do if they wish to discontinue CHC or change their contraception (see Section 15).

Verbal information-giving should be supported by a comprehensive leaflet or direction to a trusted
website.
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Box 4: Women using combined hormonal contraception: key indications for medical review
Key symptoms that should prompt women to seek urgent medical review► Calf pain, swelling and/or redness► Chest pain and/or breathlessness and/or coughing up blood► Loss of motor or sensory function
Key symptoms that should prompt women to seek medical review► Breast lump, unilateral nipple discharge, new nipple inversion, change in breast skin
► New onset migraine► New onset sensory or motor symptoms in the hour preceding onset of migraine► Persistent unscheduled vaginal bleeding
New medical diagnoses that should prompt women to seek advice from theircontraceptive provider (and review of the suitability of CHC)
► High blood pressure2► High body mass index (>35 kg/m )► Migraine or migraine with aura
► Deep vein thrombosis or pulmonary embolism► Blood clotting abnormality► Antiphospholipid antibodies► Angina, heart attack, stroke or peripheral vascular disease► Atrial fibrillation► Cardiomyopathy► Breast cancer or breast cancer gene mutation► Liver tumour► Symptomatic gallstones
12.6 Duration of CHC prescription
Clinical recommendationC

HCP can prescribe up to 12 months’ supply of CHC for women who are initiating or
continuing CHC.

In line with the WHO Selected Practice Recommendations85 the GDG advises that provision of up toa 1-year supply of CHC may be appropriate depending on the woman’s preference and anticipateduse. Restriction of the length of supply could result in unwanted discontinuation of the method
and increased risk of pregnancy. Although there could be some potential wastage, cost and useof resource associated with frequent follow-up appointments are avoided. It may be appropriate
to provide a more limited supply (e.g. 3 months) for women who would benefit from returning for afollow-up visit (e.g. women with pre-existing significant medical conditions).
12.6.1 Combined oral contraception
A systematic review364 suggested that provision of a greater number of packs of
COC was associated with increased rates of continuation. Studies that compared
provision of 1 vs 12 packs, 1 vs 12 or 13 packs, or 3 vs 7 seven packs found increased
continuation of pill use among women provided with more pill packs.365–367 Provisionof more pills packs was associated with fewer pregnancy tests, fewer pregnancies,
and lower costs for users. However, a greater number of pill packs (i.e. 13 packs vs
3 packs) was also associated with increased pill wastage in one study.365

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12.6.2 Combined transdermal patch
No evidence was identified on which to base recommendations for the number of packs of patches
provided but once a woman is established on CTP, provision of a 12-month supply is reasonable.
12.6.3 Combined vaginal ring
Following manufacture, supplies of Nuvaring have to be kept refrigerated. After dispensing,Nuvaring can be stored at room temperature and used within a maximum of 4 months. Therefore
no more than one pack of three Nuvaring can be provided at any one time. Arrangements should
be made for repeat prescription to prevent users routinely having to return to the provider morethan once per year. SyreniRing does not required refrigeration and a one-year supply can bedispensed.

13. What follow-up is required for women continuing withuse of CHC?
13.1 What follow-up arrangements are appropriate?
Clinical recommendation✓

Women should be advised that routine annual review of their contraception isrecommended during CHC use.

The GDG recommend that women who continue CHC should be routinely reviewed on an annual
basis; routine follow-up, including annual recording of blood pressure and BMI measurement may beachieved without a face-to-face consultation. Women with certain existing medical conditions may
benefit from attending more frequently or for face-to-face follow-up.
All women should be advised to return or seek professional advice at any time if they are experiencing
troublesome side effects, have a significant new health event, start new medication, wish to
discontinue CHC or to discuss alternative methods.
There is no evidence that frequent follow-up improves correct or continued use of
CHC. A systematic review368 which identified two studies found little difference in
effective contraceptive use between adolescents who had (telephone) contact with
their provider and those who did not. A randomised trial of daily text message reminders
among women with a mean age of 22 years did not improve OC adherence.132

Evidencelevel 2-13.1.1 What should be done at CHC follow-up?
Clinical recommendation✓

Medical eligibility, drug history, method adherence and method satisfaction should
be reassessed at follow up. BMI and blood pressure should be recorded.

Routine follow-up has long been considered an essential aspect of ensuring the safety ofcontraceptive use and a way to ensure adherence. At follow-up, medical eligibility should be
rechecked, drug history updated, method adherence and method satisfaction assessed, andalternative contraceptive options considered. Women should be reminded about signs, symptoms,
health events and changes in medication that should prompt them to seek medical review.
Weight and blood pressure have been the two parameters considered most important with respect
to routine follow-up.

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Weight/BMI: A systematic review339 identified no large effect of CHC use on weightgain. In one matched cohort study of adolescents using COC published since thisreview,369 BMI increased by a mean of 0.04 kg/m2 per month among COC users versus
0.025 kg/m2 per month among controls. If BMI is ≥35 kg/m2 at follow-up, women should
be advised to switch to an alternative method of contraception.

Evidencelevel 2-

Blood pressure: A systematic review370 of five studies, with methodologicallimitations, examining blood pressure after CHC initiation, generally showed that
only a small percentage of women (2% in the largest study) develop hypertension
between 1 and 24 months after starting hormonal contraception. One matchedcohort study published since this review found no significant changes in bloodpressure among adolescents using COC during 18 months of follow -up whencompared with controls.369 No studies were identified that examined changes inblood pressure with time among patch users. A small study of 18 women suggested
that in normotensive women, the CVR slightly increased 24-hour ambulatory bloodpressure after six cycles of use.371 The increase was statistically significant but
small (mean 24-hour blood pressure increased by 2.69 ± 5.35 mmHg) and clinicalrelevance is uncertain.

Evidencelevel 2-Since hypertension increases the risk of MI and stroke, the GDG recommend thata woman wishing to continue using CHC should have her blood pressure checked
annually to ensure that it remains within the acceptable range.
13.2 Online and remote provision of CHC
At the time of publication of this guideline, little has been published in the peer-reviewed literature
about remote prescribing of CHC. A number of pilot projects have been started but evaluation isstill awaited.372
The recommendation of the GDG is that both remote and online prescribing are suitable for CHC.
The checks that are suggested above can all take place remotely, and therefore a face-to-faceconsultation is not necessary for safe prescribing.
The General Medical Council (GMC) provides guidance on safe prescribing for doctors. 373 If thedoctor has adequate knowledge of the patient’s health and is satisfied that the medicine will serve
the patient’s needs, remote prescribing is acceptable. For CHC, doctors prescribing remotely mustensure that the woman does not have any health conditions categorised as UKMEC 3 or UKMEC
4 for CHC. A recent blood pressure measurement taken by a HCP or obtained at a self-testingstation (e.g. in a general practitioner surgery) is acceptable for the purposes of prescribing CHC andmay be self-reported by the woman. Recent height and weight measurements may be taken andself-reported by the woman.
For other information, self-completed questionnaires have been shown to be safe and adequate,
as outlined in Section 12.1.1. As more evidence becomes available about online prescribing,
the FSRH Clinical Effectiveness Unit (CEU) will consider whether further guidance becomesappropriate.

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14. What specific advice is required for women using CHC?
14.1 CHC use during travel
Clinical recommendation

C

Women using CHC should be advised about reducing periods of immobility during
travel.

14.1.1 VTE risk during travel
Long duration travel is a weak risk factor for VTE. The risk is not confined to air travel Evidence(although most of the evidence relates to flying), increases with the duration of travel level 2+
and with the presence of pre-existing risk factors for VTE. The British Society for
Haematology bases its recommendations on a systematic review of the evidence. 374
Data from prospective studies which evaluated air travellers for deep vein thrombosis(DVT) before and after their journeys suggest an incidence of DVT of 1 in 560 people
travelling by air for 8 hours. Retrospective studies suggest that pulmonary embolism isextremely rare in flights of <8 hours but that the risk is associated with the duration of
travel (5/million in flights >12 hours) and with pre-existing risk factors for VTE. Thereis indirect evidence that maintaining mobility during travel is a reasonable precaution,
while for people without pre-existing risk factors, compression stockings and antiplatelet drugs (aspirin) are not indicated.
Case reports have suggested that CHC use could be associated with further increased
risk of VTE associated with travel.375 The GDG recommends that women using CHC
should minimise immobility during travel, but existing evidence is inadequate to allow any
recommendation to be made about use of compression stockings or anti-platelet drugs.
14.1.2 Adherence to CHC when crossing time zones
Women travelling through different time zones should be reminded of the importance of taking their
COC pill approximately 24 hours after their most recent pill (i.e. using the time of day in the time zone
in which the last pill was taken as a reference point rather than local time).
A COC is missed when it has been more than 24 hours since the pill should have been taken. Twopills have been missed when it has been more than 72 hours since the last pill was taken. Refer to
Section 8.1 for advice on missed CHC.
14.2 CHC use at high altitude
Clinical recommendation

D

Women trekking to high altitudes (above 4500 m or 14 500 feet) for periods of morethan 1 week may be advised to consider switching to a safer alternative contraceptive
method.

Exposure to high altitude results in an increase in erythropoiesis and in the risk of thrombosis.

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Environmental factors associated with climbing to high altitude (hypoxia, dehydration, low Evidence
temperature and enforced immobility due to bad weather) all contribute to the risk. Despite level 4
lack of robust evidence and few reported cases, experts recommend that women should
consider avoiding CHC if they are to spend more than a week above 4500 m (14 764 feet).376
Below this altitude, use of CHC is likely to be safe in a healthy, active, non-smoking woman
with no personal or family history of venous thrombosis or thrombophilia.
14.3 Surgery/periods of immobilisation
Clinical recommendation

D

Women should be advised to stop CHC and to switch to an alternative contraceptive
method at least 4 weeks prior to planned major surgery or expected period of limited
mobility.

Women who are immobile or have restricted mobility for an extended period of time (due tosurgery or other reasons) are at increased risk for VTE. This risk may be further increased withuse of CHC.
With regard to the use of CHC by women undergoing surgery, the British National Evidence
Formulary377 advises that “estrogen-containing contraceptives should preferably be level 4
discontinued (and adequate alternative contraceptive arrangements made) 4 weeks before
major elective surgery and all surgery to the legs or surgery which involves prolonged
immobilisation of a lower limb; they should normally be recommenced at the first menses
occurring at least 2 weeks after full mobilisation. A progestogen-only contraceptive may
be offered as an alternative and the estrogen-containing contraceptive restarted after
mobilisation. When discontinuation of an estrogen-containing contraceptive is not possible,
e.g. after trauma or if a patient admitted for an elective procedure is still on an estrogencontaining contraceptive, thromboprophylaxis (with unfractionated or low molecular weight
heparin and graduated compression hosiery) is advised. These recommendations do not
apply to minor surgery with short duration of anaesthesia (e.g. laparoscopic sterilisation or
tooth extraction), or to women using oestrogen-free hormonal contraceptives.”

15. What recommendations are there regarding stopping CHC?
15.1 How long can women use CHC?
Clinical recommendation

D

CHC can be used by medically eligible women for contraception until age 50 years.

15.1.1 Use of CHC by women aged over 40 years
Women may use CHC for contraception until age 50 years provided there areno contraindications as outlined in UKMEC. 96 After age 50 years, the risks of CHC
use generally outweigh the contraceptive benefits and women should be advised toswitch from CHC to a POP, subdermal implant, LNG-releasing IUS or a non-hormonal
contraceptive method.378 Women taking CHC for non-contraceptive benefits who wish
to continue use after the age of 50 years should be considered on an individual basis.
See FSRH Guideline Contraception for Women Aged Over 40 Years.378

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15.1.2 Duration of CHC use
For medically eligible women under the age of 50 years, there is no arbitrary maximum length oftime for which CHC can be used. Repeated starting and stopping of CHC should be discouraged
because VTE risk is highest in the months after initiation or when restarting after a break of atleast 1 month (see Section 10.1).
15.2 Switching to another method of contraception
Women who wish to switch to a different method of contraception should be advised
whether additional contraceptive precaution (i.e. barrier methods/ abstinence) is required, and for
how long (see Table 7).
Table 7: Recommendations for additional contraceptive precautions when switching fromcombined hormonal contraception to another method
Current CHC use

Switching to(used correctly)

CHC

POP

DMPA

IMP

LNG-IUD

Week 2 or 3 (andsubsequent weeks ofcontinuous CHC use)

None

None

None

None

If day 1 of HFI: None
None

If day 2 of HFI
follow advice
for day 3-7
below

OR
Day 1-2 of HFI
Week 1after HFI
OR
Day 3-7of HFI

Cu-IUDNo UPSI since
start of the HFICondoms for
7 daysUPSI since
the start of
the HFI

Restart/continue CHC until
active pills, patch or ringused for 7 consecutive days
THEN
Switch as for weeks 2 or 3

Condoms for
2 daysCondoms for
7 daysCondoms for
7 daysCondoms for
7 daysNone

Start immediatelyAND
restart/continue CHC until active pills, patchor ring used for 7 consecutive days

None

CHC, combined hormonal contraception; Cu-IUD, copper intrauterine device; DMPA, depot medroxyprogesterone acetate(progestogen-only injectable); HFI, hormone-free interval; IMP, progestogen-only implant; LNG-IUS, levonorgestrelreleasing intrauterine system; POP, progestogen-only pill; UPSI, unprotected sexual intercourse.

15.3 Planning pregnancy
15.3.1 Return of fertility
Women who wish to conceive after stopping contraception should be advised that after stopping
CHC there is no significant delay in return to fertility and conception rates are comparable to thoseamong women stopping other contraceptive methods or using no contraception (see Section 11.6).
Folic acid supplementation can be started prior to stopping CHC.
15.3.2 Preconception care
Refer to the FSRH Clinical Statement Preconception Care.379
15.3.3 Unplanned pregnancy during CHC use
The available evidence suggests that fetal exposure to CHC is not associated with fetal abnormality(see Section 6.3.2). See FSRH Guideline Quick Starting Contraception.86
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16. Use of CHC in the perimenopause
16.1 Use of CHC as an alternative to HRT
Clinical recommendation

D

CHC can be considered for use by medically eligible women until age 50 as analternative to HRT for relief of menopausal symptoms and prevention of loss ofbone mineral density as well as for contraception.

Use of CHC can suppress menopausal symptoms, regulate bleeding and maintain BMD in theperimenopause (see Section 9). CHC can therefore be used by eligible women aged under age
50 years as an alternative to HRT as well as for contraception. During use of CHC, serum levels of
estradiol, FSH and LH are suppressed and cannot be used to inform advice regarding menopausal
status.380,381
Estradiol/nomegestrol acetate and estradiol valerate/dienogest COC formulations contain estradiol
rather than the synthetic EE present in most COC. They share some similarities with HRT preparations,rather than EE COC, so have theoretical safety benefits for women aged over 40 years. However,evidence relating to specific benefits or risks associated with their use is not yet available and
FSRH advice relating to CHC in general is currently considered to apply also to estradiol COC.
16.2 Transition to HRT
Women using CHC should be advised to switch to a suitable alternative method of contraception at
the age of 50 years, or if they develop medical contraindications to use of CHC, or if they prefer not to
use CHC for contraception; if HRT is indicated for control of menopausal symptoms or maintenanceof BMD it can be used alongside the (non-CHC) contraceptive method. See FSRH Guideline
Contraception for Women Aged Over 40 Years.378

Recommendations for future research
►

►
►
►
►
►

Safety, effectiveness and acceptability of COC regimens that have estrogen-only pills in place ofa HFISafety and effectiveness of CHC regimens with shortened HFISafety, effectiveness and acceptability of continuous CHC regimens
Comparison of bleeding patterns with continuous use of different CHC regimens
Safety and effectiveness of estradiol COC compared to EE COC
Safety, feasibility and acceptability of COC provision (initiation/continuation) at the pharmacy

Considerations for implementation of this guideline►►►

Patient group direction (PGD) for tailored COC regimens
Training and resources to support HCPs discuss tailored regimens with womenPatient resources to support safe and effective tailored CHC use

Useful links►

Family Planning Association (FPA)

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76 Loudon NB, Foxwell M, Potts DM, et al. Acceptability of an oral contraceptive that reduces thefrequency of menstruation: the tri-cycle pill regimen. Br Med J 1977;2:487–90.
77 den Tonkelaar I, Oddens BJ. Preferred frequency and characteristics of menstrual bleeding in
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78 Wiegratz I, Hommel HH, Zimmermann T, et al. Attitude of German women and gynecologists
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88 Killick S, Eyong E, Elstein M. Ovarian follicular development in oral contraceptive cycles. Fertil
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304 Loder EW, Buse DC, Golub JR. Headache as a side effect of combination estrogen-progestinoral contraceptives: a systematic review. Am J Obstet Gynecol 2005;193:636–49.
305 MacGregor EA. Contraception and headache. Headache 2013;53:247–76.
306 Merz M, Kroll R, Lynen R, et al. Bleeding pattern and cycle control of a low-dose transdermal
contraceptive patch compared with a combined oral contraceptive: a randomized study.
Contraception 2015;91:113–20.
307 Endrikat J, Hite R, Bannemerschult R, et al. Multicenter, comparative study of cycle
control, efficacy and tolerability of two low-dose oral contraceptives containing 20 microg
ethinylestradiol/100 microg levonorgestrel and 20 microg ethinylestradiol/500 microg
norethisterone. Contraception 2001;64:3–10.
308 Ahrendt H-J, Makalová D, Parke S, et al. Bleeding pattern and cycle control with an estradiolbased oral contraceptive: a seven-cycle, randomized comparative trial of estradiol valerate/dienogest and ethinyl estradiol/levonorgestrel. Contraception 2009;80:436–44.
309 Hampton RM, Short M, Bieber E, et al. Comparison of a novel norgestimate/ethinyl estradiol
oral contraceptive (Ortho Tri-Cyclen Lo) with the oral contraceptive Loestrin Fe 1/20.
Contraception 2001;63:289–95.
310 Shapley M, Jordan K, Croft PR. Abnormal bleeding patterns associated with menorrhagia in
women in the community and in women presenting to primary care. Fam Pract 2007;24:532–7.
311 Fan GS, Ren M, Di W, et al. Efficacy and safety of the contraceptive vaginal ring (NuvaRing)
compared with a combined oral contraceptive in Chinese women: a 1-year randomised trial.
Eur J Contracept Reprod Health Care 2016;21:303–9.

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312 Faculty of Sexual & Reproductive Healthcare (FSRH). FSRH Clinical Guidance: Problematic
Bleeding with Hormonal Contraception. 2015. https://www.fsrh.org/Public/Documents/ceuguidance-problematic-bleeding-hormonal-contraception.aspx
313 Brache V, Faundes A. Contraceptive vaginal rings: a review. Contraception 2010;82:418–27.
314 Hampton RM, Zhang HF, Barnowski C, et al. Bleeding patterns with monophasic and triphasic
low-dose ethinyl estradiol combined oral contraceptives. Contraception 2008;77:415–9.
315 Gallo MF, Nanda K, Grimes DA, et al. 20 µg versus >20 µg estrogen combined oral
contraceptives for contraception. Cochrane Database Syst Rev 2013;CD003989.
316 Akerlund M, Rodez A, Westergaard J. Comparative profiles of reliability, cycle control andside effects of two oral contraceptive formulations containing 150 micrograms desogestrel
and either 30 micrograms or 20 micrograms ethinyl oestradiol. Br J Obstet Gynaecol
1993;100:832–8.
317 Kulier R, Helmerhorst FM, Maitra N, et al. Effectiveness and acceptability of progestogens in
combined oral contraceptives - a systematic review. Reprod Health 2004;1:1.
318 Mansour D, Verhoeven C, Sommer W, et al. Efficacy and tolerability of a monophasic
combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol in a 24/4
regimen, in comparison to an oral contraceptive containing ethinylestradiol and drospirenone
in a 21/7 regimen. Eur J Contracept Reprod Health Care 2011;16:430–43.
319 Westhoff C, Kaunitz AM, Korver T, et al. Efficacy, safety, and tolerability of a monophasic oral
contraceptive containing nomegestrol acetate and 17β-estradiol: a randomized controlled trial.
Obstet Gynecol 2012;119:989–99.
320 Guillebaud J. Practical prescribing of the combined oral contraceptive pill. In: Practicalprescribing of the combined oral contraceptive pill. Editor(s) Filshie M, Guillebaud J. London:
Butterworth & Co. 1989. 69–93.
321 Oddens BJ. Women’s satisfaction with birth control: a population survey of physical andpsychological effects of oral contraceptives, intrauterine devices, condoms, natural familyplanning, and sterilization among 1466 women. Contraception 1999;59:277–86.
322 Rosenberg MJ, Waugh MS. Oral contraceptive discontinuation: a prospective evaluation of
frequency and reasons. Am J Obstet Gynecol 1998;179:577–82.
323 Schaffir J, Worly BL, Gur TL. Combined hormonal contraception and its effects on mood: acritical review. Eur J Contracept Reprod Health Care 2016;21:347–55.
324 Graham CA, Ramos R, Bancroft J, et al. The effects of steroidal contraceptives on thewell-being and sexuality of women: a double-blind, placebo-controlled, two-centre study of
combined and progestogen-only methods. Contraception 1995;52:363–9.
325 Zethraeus N, Dreber A, Ranehill E, et al. A first-choice combined oral contraceptive influences
general well-being in healthy women: a double-blind, randomized, placebo-controlled trial.
Fertil Steril 2017;107:1238–45.

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326 Wimberly YH, Cotton S, Wanchick AM, et al. Attitudes and experiences with levonorgestrel
100 microg/ethinyl estradiol 20 microg among women during a 3-month trial. Contraception
2002;65:403–6.
327 Duke JM, Sibbritt DW, Young AF. Is there an association between the use of oral contraception
and depressive symptoms in young Australian women? Contraception 2007;75:27–31.
328 Toffol E, Heikinheimo O, Koponen P, et al. Hormonal contraception and mental health: resultsof a population-based study. Hum Reprod 2011;26:3085–93.
329 Toffol E, Heikinheimo O, Koponen P, et al. Further evidence for lack of negative associations
between hormonal contraception and mental health. Contraception 2012;86:470–80.
330 Keyes KM, Cheslack-Postava K, Westhoff C, et al. Association of hormonal contraceptive usewith reduced levels of depressive symptoms: a national study of sexually active women in the
United States. Am J Epidemiol 2013;178:1378–88.
331 Skovlund CW, Mørch LS, Kessing LV, et al. Association of Hormonal Contraception With
Depression. JAMA Psychiatry 2016;73:1154–62.
332 Skovlund CW, Mørch LS, Kessing LV, et al. Association of Hormonal Contraception With
Suicide Attempts and Suicides. Am J Psychiatry 2018;175:336–42.
333 Vessey MP, Villard-Mackintosh L, McPherson K, et al. Mortality among oral contraceptive
users: 20 year follow up of women in a cohort study. BMJ 1989;299:1487–91.
334 Beral V, Hermon C, Kay C, et al. Mortality associated with oral contraceptive use: 25 year
follow up of cohort of 46 000 women from Royal College of General Practitioners’ oral
contraception study. BMJ 1999;318:96–100.
335 Colditz GA. Oral contraceptive use and mortality during 12 years of follow-up: the Nurses’
Health Study. Ann Intern Med 1994;120:821–6.
336 Shahnazi M, Farshbaf Khalili A, Ranjbar Kochaksaraei F, et al. A comparison of second andthird generations combined oral contraceptive pills’ effect on mood. Iran Red Crescent Med J
2014;16:e13628.
337 Sangthawan M, Taneepanichskul S. A comparative study of monophasic oral contraceptives
containing either drospirenone 3 mg or levonorgestrel 150 microg on premenstrual symptoms.
Contraception 2005;71:1–7.
338 Kelly S, Davies E, Fearns S, et al. Effects of oral contraceptives containing ethinylestradiol
with either drospirenone or levonorgestrel on various parameters associated with well-beingin healthy women: a randomized, single-blind, parallel-group, multicentre study. Clin Drug
Investig 2010;30:325–36.
339 Gallo MF, Lopez LM, Grimes DA, et al. Combination contraceptives: effects on weight.
Cochrane Database Syst Rev 2014;CD003987.
340 Pastor Z, Holla K, Chmel R. The influence of combined oral contraceptives on female sexualdesire: a systematic review. Eur J Contracept Reprod Health Care 2013;18:27–43.

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341 Čiaplinskienė L, Žilaitienė B, Verkauskienė R, et al. The effect of a drospirenone-containing
combined oral contraceptive on female sexual function: a prospective randomised study. Eur J
Contracept Reprod Health Care 2016;21:395–400.
342 Duijkers IJM, Klipping C, Grob P, et al. Effects of a monophasic combined oral contraceptive
containing nomegestrol acetate and 17 beta-oestradiol on ovarian function in comparison to amonophasic combined oral contraceptive containing drospirenone and ethinylestradiol. Eur J
Contracept Reprod Health Care 2010;15:314–25.
343 Kroll R, Seidman L, Ricciotti N, et al. A phase 1, multicentre, open-label study to evaluateovarian follicular activity and hormone levels with an extended-regimen combined oral
contraceptive with low-dose ethinyl estradiol supplementation. Eur J Contracept Reprod
Health Care 2015;20:249–58.
344 Barnett C, Hagemann C, Dinger J, et al. Fertility and combined oral contraceptives unintended pregnancies and planned pregnancies following oral contraceptive use - resultsfrom the INAS-SCORE study. Eur J Contracept Reprod Health Care 2017;22:17–23.
345 Barnhart K, Mirkin S, Grubb G, et al. Return to fertility after cessation of a continuous oral
contraceptive. Fertil Steril 2009;91:1654–6.
346 Mansour D, Gemzell-Danielsson K, Inki P, et al. Fertility after discontinuation of contraception:
a comprehensive review of the literature. Contraception 2011;84:465–77.
347 Axmon A, Rylander L, Albin M, et al. Factors affecting time to pregnancy. Hum Reprod
2006;21:1279–84.
348 Hassan J, Kulenthran A, Thum YS. The return of fertility after discontinuation of oral
contraception in Malaysian women. Med J Malaysia 1994;49:348–50.
349 Kaplan B, Nahum R, Yairi Y, et al. Use of various contraceptive methods and timeof conception in a community-based population. Eur J Obstet Gynecol Reprod Biol
2005;123:72–6.
350 Linn S, Schoenbaum SC, Monson RR, et al. Delay in conception for former “pill” users. JAMA
1982;247:629–32.
351 Mikkelsen EM, Riis AH, Wise LA, et al. Pre-gravid oral contraceptive use and time topregnancy: a Danish prospective cohort study. Hum Reprod 2013;28:1398–405.
352 Vessey MP, Wright NH, McPherson K, et al. Fertility after stopping different methods ofcontraception. Br Med J 1978;1:265–7.
353 Cronin M, Schellschmidt I, Dinger J. Rate of pregnancy after using drospirenone and otherprogestin-containing oral contraceptives. Obstet Gynecol 2009;114:616–22.
354 Farrow A, Hull MGR, Northstone K, et al. Prolonged use of oral contraception before aplanned pregnancy is associated with a decreased risk of delayed conception. Hum Reprod
2002;17:2754–61.

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355 Wiegratz I, Mittmann K, Dietrich H, et al. Fertility after discontinuation of treatment with anoral contraceptive containing 30 microg of ethinyl estradiol and 2 mg of dienogest. Fertil Steril
2006;85:1812–9.
356 Grossman D, Fernandez L, Hopkins K, et al. Accuracy of self-screening for contraindications
to combined oral contraceptive use. Obstet Gynecol 2008;112:572–8.
357 Shotorbani S, Miller L, Blough DK, et al. Agreement between women’s and providers’assessment of hormonal contraceptive risk factors. Contraception 2006;73:501–6.
358 Doshi JS, French RS, Evans HER, et al. Feasibility of a self-completed history questionnaire
in women requesting repeat combined hormonal contraception. J Fam Plann Reprod HealthCare 2008;34:51–4.
359 Chin-Quee D, Ngadaya E, Kahwa A, et al. Women’s ability to self-screen for contraindications
to combined oral contraceptive pills in Tanzanian drug shops. Int J Gynaecol Obstet
2013;123:37–41.
360 Tepper NK, Curtis KM, Steenland MW, et al. Blood pressure measurement prior to initiating
hormonal contraception: a systematic review. Contraception 2013;87:631–8.
361 Tepper NK, Curtis KM, Steenland MW, et al. Physical examination prior to initiating hormonal
contraception: a systematic review. Contraception 2013;87:650–4.
362 Tepper NK, Steenland MW, Marchbanks PA, et al. Laboratory screening prior to initiating
contraception: a systematic review. Contraception 2013;87:645–9.
363 Faculty of Sexual & Reproductive Healthcare (FSRH). Sexual and Reproductive Health for
Individuals with Inflammatory Bowel Disease. 2016.
https://fsrh.org/Public/Documents/ceu-clinical-guidance-srh-ibd.aspx
364 Steenland MW, Rodriguez M-I, Marchbanks PA, et al. How does the number of oral
contraceptive pill packs dispensed or prescribed affect continuation and other measures ofconsistent and correct use? A systematic review. Contraception 2013;87:605–10.
365 Foster DG, Parvataneni R, de Bocanegra HT, et al. Number of oral contraceptive pill packages
dispensed, method continuation, and costs. Obstet Gynecol 2006;108:1107–14.
366 Foster DG, Hulett D, Bradsberry M, et al. Number of oral contraceptive pill packages
dispensed and subsequent unintended pregnancies. Obstet Gynecol 2011;117:566–72.
367 White KO, Westhoff C. The effect of pack supply on oral contraceptive pill continuation: arandomized controlled trial. Obstet Gynecol 2011;118:615–22.
368 Steenland MW, Zapata LB, Brahmi D, et al. The effect of follow-up visits or contacts after
contraceptive initiation on method continuation and correct use. Contraception 2013;87:625–30.
369 Kharbanda EO, Parker ED, Sinaiko AR, et al. Initiation of oral contraceptives and changes inblood pressure and body mass index in healthy adolescents. J Pediatr 2014;165:1029–33.

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370 Steenland MW, Zapata LB, Brahmi D, et al. Appropriate follow up to detect potential adverse
events after initiation of select contraceptive methods: a systematic review. Contraception
2013;87:611–24.
371 Cagnacci A, Zanin R, Napolitano A, et al. Modification of 24-h ambulatory blood pressureand heart rate during contraception with the vaginal ring: a prospective study. Contraception
2013;88:539–43.
372 Gawron LM, Turok DK. Pills on the World Wide Web: reducing barriers through technology.
Am J Obstet Gynecol 2015;213:500.e1-4.
373 General Medical Council (GMC). Remote prescribing via telephone, video-link or online.
https://www.gmc-uk.org/ethical-guidance/ethical-guidance-for-doctors/prescribing-andmanaging-medicines-and-devices/remote-prescribing-via-telephone-video-link-or-online.
374 Watson HG, Baglin TP. Guidelines on travel-related venous thrombosis. Br J Haematol
2011;152:31–4.
375 Martinelli I, Taioli E, Battaglioli T, et al. Risk of venous thromboembolism after air travel:interaction with thrombophilia and oral contraceptives. Arch Intern Med 2003;163:2771–4.
376 Hillebrandt D, Meijer H. Consensus Statement of the UIAA Medical Commission. Vol 14:
Contraception and Perioud Control at Altitude. Intended for Physicians and Other Non-medical
Interested Persons. 2009. https://www.thebmc.co.uk/Download.aspx?id=473
377 MedicinesComplete. British National Formulary (BNF) Online. British Medical Association andRoyal Pharmaceutical Society; https://www.bnf.org/
378 Faculty of Sexual & Reproductive Healthcare (FSRH). Contraception for women aged over
40 years. 2017. https://www.fsrh.org/Public/Documents/fsrh-guidance-contraception-forwomen-aged-over-40-years-2017.aspx
379 Faculty of Sexual & Reproductive Healthcare (FSRH). CEU Statement: Pre-conception
Care (August 2016). 2016. https://fsrh.org/Public/Documents/pre-conception-care-careceu-statement-august-2016.aspx
380 Beksinska ME, Smit JA, Kleinschmidt I, et al. Bone mineral density in women aged 40-49
years using depot-medroxyprogesterone acetate, norethisterone enanthate or combined oral
contraceptives for contraception. Contraception 2005;71:170–5.
381 Hemrika DJ, Slaats EH, Kennedy JC, et al. Pulsatile luteinizing hormone patterns in long termoral contraceptive users. J Clin Endocrinol Metab 1993;77:420–6.

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Appendices
Appendix 1: FSRH Clinical Guideline Development Process
Who has developed the guideline?
This guideline is produced by the Clinical Effectiveness Unit (CEU) with support from the ClinicalEffectiveness Committee (CEC) of the Faculty of Sexual & Reproductive Healthcare (FSRH). The
FSRH is a registered charitable organisation which funds the development of its own clinical guidelines.
NHS Lothian is contracted to host the CEU in the Chalmers Centre and to provide the CEU’s services
using ring-fenced funding from the FSRH. No other external funding is received. Chalmers Centre
supports the CEU in terms of accommodation, facilities, education, training and clinical advice forthe members’ enquiry service. As an organisation, NHS Lothian has no editorial influence over
CEU guidelines, although staff members may be invited to join the CEU’s multidisciplinary guideline
development groups (GDGs) in an individual professional capacity.
Development of the guideline was led by the secretariat (CEU staff) and involved the intended usersof the guidelines (contraception providers) and patient/service user representatives as part of amultidisciplinary group. The scope of the guideline was informed by a scoping survey conductedamong members of the FSRH and among service users from two sexual and reproductive healthservices (Sandyford Sexual Health Service, Glasgow and Gwent, Wales) across the UK. The first draftof the guideline was produced based on the final scope of the guideline agreed by the GDG. The firstdraft of the guideline (version 0.1) was reviewed by the GDG and a revised draft guideline (version0.2) was produced in response to comments received, after which the it was sent to internationaland UK-based external independent reviewers suggested by the GDG at the face-to-face meeting.
A further revision generated a version of the draft guideline (version 0.3) which was placed on the
FSRH website for public consultation between 8 February and 7 March 2017. The revised draft
guideline (version 0.4) was sent to the GDG for final comments and to reach consensus on therecommendations (details of this process are given later).
Below is the list of contributors involved in the development of this clinical guideline.
Guideline Development Group (GDG) Secretariat►

Dr Sarah Hardman

Co-Director, Clinical Effectiveness Unit►

Professor Sharon Cameron

Co-Director, Clinical Effectiveness Unit►

Dr Zhong Eric Chen

Researcher, Clinical Effectiveness Unit►

Mrs Valerie Warner Findlay

Researcher, Clinical Effectiveness Unit

Multidisciplinary group►

Dr Ailsa Gebbie

Consultant Gynaecologist (Chalmers Centre, NHS Lothian,
Edinburgh)►

Professor Anna Glasier

Honorary Professor (University of Edinburgh)►

Dr Zara Haider

Consultant in Sexual and Reproductive Healthcare (Kingston
Hospital, Surrey)►

Dr Susanna Hall

Consultant in Sexual and Reproductive Health (Gloucester)►

Professor Philip Hannaford

NHS Grampian Chair of Primary Care►

Mrs Michelle Jenkins

Advance Nurse Practitioner (Chelsea and Westminster
Hospital NHS Foundation Trust)

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Multidisciplinary group►

Dr Diana Mansour

Consultant in Community Gynaecology and Reproductive
Healthcare, Head of Clinical Service, Sexual Health(Newcastle upon Tyne); FSRH Vice-President Clinical Quality►

Ms Anastasia Mezecka

Patient Representative►

Patient Representative 2*

Patient Representative►

Ms Claire Nicol

Advance Nurse Practitioner (Chalmers Centre, NHS Lothian,
Edinburgh)►

Dr Rudiger Pittrof

Consultant in Community Sexual Health and HIV (Guy’s andSt Thomas’ NHS Foundation Trust, London)►

Dr Janine Simpson

Community Sexual and Reproductive Health Trainee(Sandyford Sexual Health Service, NHS Greater Glasgow
and Clyde)►

Dr Penny Sinclair

General Practitioner (Bevan Healthcare Medical Practice,
Bradford)*Patient Representative has chosen to remain anonymous.

The FSRH CEU wish to acknowledge the contribution made by Dr Katie Boog who worked onliterature review for and development of the sections on combined hormonal contraception andcancer risk.
Independent reviewers►

Associate Professor Kirsten Black(Australia)

Joint Head of Discipline of Obstetrics, Gynaecology
and Neonatology (University of Sydney, Australia)►

Dr Monica Dragoman (USA)

Associate Medical Director (Planned Parenthood of
New York City)►►

Professor Oskari Heikinheimo(Finland)Professor, Department of Obstetrics & Gynecology(University of Helsinki)►

Dr Helena Kopp Kallner (Sweden)

Senior Consultant, Obstetrics and Gynecology(Danderyd Hospital); Department of Women’s andChildren’s Health (Karolinska Institutet)►

Professor Judith Stephenson (UK)

Margaret Pyke Professor of Sexual & Reproductive
Health (University College London)

Declaration of interests
None of the individuals involved had competing interests that prevented their active participation in
the development of this guideline.
Patient involvement
Service users from two sexual and reproductive health services (Sandyford Sexual Health Service,
Glasgow and Gwent, Wales) across the UK were involved in providing feedback on the scope of theguideline.

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Two patient representatives were involved consistently throughout the development process. They
provided valuable feedback on multiple drafts of the guideline; their input informed and supported
content and the development of recommendations.
Public consultation contributors
We would like to thank the contributors who provided their valuable feedback during the public
consultation.
Guideline development methodology
This FSRH guideline was developed in accordance with the standard methodology for developing
FSRH clinical guidelines (outlined in the FSRH’s Framework for Clinical Guideline Development
which can be accessed here). The methodology used in the development of this guideline has been
accredited by the National Institute for Health and Care Excellence (NICE).
Systematic review of evidence
A systematic review of the literature was conducted to identify evidence to answer the clinicalquestions formulated and agreed by the GDG. Searches were performed using relevant medical
subject headings and free-text terms using the following databases: PubMed, EMBASE, CochraneCentral Register of Controlled Trials, Cochrane Database of Systematic Reviews, the CumulativeIndex to Nursing and Allied Health Literature (CINAHL) and POPLINE ®. Further, the National
Guideline Clearinghouse (NGC) and Scottish Intercollegiate Guideline Network (SIGN) were also
used to identify relevant guidelines produced by other organisations; these guidelines were checked
to identify missing evidence. No language restrictions were applied to the searches.
Search date: The databases were initially searched up to 7 March 2017. The evidence identified up
to this point was used to develop the first draft of the guideline. The searches were re-run up to 27
August 2018 to check additional evidence published since the initial search. Any evidence publishedafter this date was not considered for inclusion.
Search strategy: The literature search was performed separately for the different sub -categories
covered in this clinical guideline.
Articles identify from the search were screened by title and abstract and full-text copies were obtained
if the articles addressed the clinical questions relevant to the guideline. A full critical appraisal of eacharticle was conducted. Studies that did not report relevant outcomes or were not relevant to theclinical questions were excluded.
Synthesis of evidence and making clinical recommendation
The recommendations are graded (A, B, C, D and Good Practice Point) according to the level ofevidence upon which they are based. The highest level of evidence that may be available depends
on the type of clinical question asked. The CEU adopts the comprehensive methodology developedby the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) to assess
the strength of the evidence collated and for generating recommendations from evidence.

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The evidence used in this guideline was graded using the scheme below and the recommendations
formulated in a similar fashion with a standardised grading scheme.
Classification of evidence levels

Grades of recommendations

1++

High-quality systematic reviews ormeta-analysis of randomised controlled trials (RCTs) or RCTs with avery low risk of bias.

1+

Well-conducted systematic reviews ormeta-analysis of RCTs or RCTs with alow risk of bias.

1-

Systematic reviews or meta-analysis
of RCTs or RCTs with a high risk of
bias.

2++

2+
23

High-quality systematic reviews ofcase-control or cohort studies or highquality case-control or cohort studies
with a very low risk of confounding,bias or chance and a high probability
that the relationship is causal.
Well-conducted case-control or cohort
studies with a low risk of confounding,bias or chance and a moderate
probability that the relationship iscausal.
Case-control or cohort studies witha high risk of confounding, bias orchance and a significant risk that therelationship is not causal.
Non-analytical studies
report, case series).
Expert opinions.

4

(e.g.

At least one systematic review,meta-analysis or RCT rated as 1++,and directly applicable to the target
population; or

A

B

C

A systematic review of RCTs ora body of evidence consisting
principally of studies rated as 1+,
directly applicable to the target
population
anddemonstrating
overall consistency of results.
A body of evidence including studies
rated as 2++ directly applicable to thetarget population and demonstrating
overall consistency of results; orExtrapolated evidence from studies
rated as 1++ or 1+.
A body of evidence including studies
rated as 2+ directly applicable to thetarget population and demonstrating
overall consistency of results; orExtrapolated evidence from studies
rated as 2++.
Evidence level 3 or 4; orExtrapolated evidence from studies
rated as 2+.

D

case

✓

Good Practice Points based on theclinical experience of the guideline
development group.**On the occasion when the GDG finds there is an important practical point that they wish to emphasise but for which there
is not, nor is there likely to be, any research evidence. This will typically be where some aspect of treatment is regarded assuch sound clinical practice that nobody is likely to question it. It must be emphasised that these are NOT an alternative toevidence-based recommendations, and should only be used where there is no alternative means of highlighting the issue.

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Considerations when making recommendations
FSRH clinical guidelines are produced primarily to recommend safe and appropriate clinical practicein relation to the provision of different contraceptive methods. Therefore, when formulating therecommendations, the GDG takes into consideration the health benefits, side effects and other risks
associated with implementing the recommendations, based on the available evidence and expert
opinion. Further, the GDG takes into consideration the different financial and organisational barriers
that healthcare practitioners and services may face in the implementation of recommendations toensure that the recommendations are realistic and achievable.
Reaching consensus on the recommendations
When further revisions based on public consultation feedback have been made, members of the GDG
were asked to complete a form to indicate whether they agree or disagree with the recommendations
proposed. The consensus process is as follows:
►
►
►

►
►

►

Consensus will be reached when 80% of the GDG members agree with the recommendation.
Recommendations where consensus is not reached will be redrafted in the light of any feedback.
The recommendation consensus form will be sent again for all recommendations. Consensus will
be reached when 80% of the GDG members agree with the recommendation.
If consensus is not reached on certain recommendations, these will be redrafted once more.
If after one more round of consultation, consensus is still not reached, the recommendation will
be taken to the CEC for final decision.
Any group member who is not content with the decision can choose to have their disagreement
noted within the guideline.

Updating this guideline
Clinical guidelines are routinely due for update 5 years after publication. The decision as to whether
update of a guideline is required will be based on the availability of new evidence published since
its publication. Updates may also be triggered by the emergence of evidence expected to have an
important impact on the recommendations. The final decision on whether to carry out a full or partial
clinical guideline update is taken by the CEU in consultation with the CEC of the FSRH.

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Appendix 2: Sections of UKMEC that contain conditions that are UKMEC 3 or 4 for use of
combined hormonal contraception
Personal characteristics
Personal characteristic
Personal characteristic
UKMEC
UKMEC
Obesity

Breastfeedinga) 0 to <6 weeks postpartum

4a) BMI ≥30–34 kg/m2

2b) ≥6 weeks to <6 months (primarily
breastfeeding)2b) BMI ≥35 kg/ m2

3c) ≥6 months postpartum

1

History of bariatric surgerya) With BMI <30 kg/ m2

1

Postpartum (in non-breastfeeding women)b) With BMI ≥30-34 kg/m2

2a) 0 to <3 weeksc) With BMI ≥35 kg/m2

3(i) With other risk factors for VTE*

4

Organ transplant(ii) Without other risk factors

3a) Complicated: graft failure (acute or
chronic), rejection, cardiac allograft
vasculopathy3b) Uncomplicated2b) 3 to <6 weeks(i) With other risk factors for VTE*

3(ii) Without other risk factors

2c) ≥6 weeks

BMI, body mass index.

1

Smokinga) Age <35 years

2b) Age >35 years(i) <15 cigarettes/day

3(ii) ≥15 cigarettes/day

4(iii) Stopped smoking <1 year

3(iv) Stopped smoking ≥1 year

2

*VTE, venous thromboembolism. In thepresence of other risk factors for VTE, such as
immobility, transfusion at delivery, BMI ≥30 kg/
m2, postpartum haemorrhage, immediately postcaesarean delivery, pre-eclampsia or smoking,use of combined hormonal contraception may
pose an additional increased risk for VTE.

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Cardiovascular
Condition

UKMEC

Hypertensiona) Adequately controlled hypertension

Condition

UKMEC

Cardiovascular disease33(i) Systolic >140–159 mmHg or
diastolic >90–99 mmHg

3

Multiple risk factors for cardiovasculardisease(suchassmoking,diabetes, hypertension, obesity anddyslipidaemias)

4

Current and history of ischaemic
heart disease4(ii) Systolic ≥160 mmHg or diastolic≥100 mmHg

4

History of high blood pressureduring pregnancy (where current
blood pressure is measurable andnormal)2

Stroke (history of cerebrovascular
accident,
includingtransientischaemic attack (TIA))

4c) Vascular diseaseb) Consistently elevated blood pressurelevels (properly taken measurements)

Valvular and congenital heart disease

Venous thromboembolism (VTE)a) History of VTE4b) Current VTE (on anticoagulants)

4a) Uncomplicated

2

b)

4

Complicated (e.g. pulmonary
hypertension, history of subacutebacterial endocarditis)

Cardiac arrhythmiasc) Family history of VTE(i) First-degree relative age <45 years

3(ii) First-degree relative age ≥45 years

2a) Atrial fibrillation

4b) Known long QT syndrome2

Cardiomyopathyd) Major surgerya) Normal cardiac function

22b) Impaired cardiac function

4e) Minor surgery without immobilisation

1

Headachesf) Immobility (unrelated to surgery) e.g.
wheelchair use, debilitating illness

3

Condition

Known thrombogenic mutations(e.g. factor V Leiden, prothrombin
mutation, Protein S, Protein C andantithrombin deficiencies)

4(i) With prolonged immobilisation

4(ii) Without prolonged immobilisation

UKMEC

Headachesa) Non-migrainous (mild or severe)b) Migraine without aura, at any age

I

C

1

2

I

C

2

3

c) Migraine with aura, at any age

4d) History (≥5 years ago) of migrainewith aura, any age

3

C, continuation; I, initiation.

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FSRH guideline: CHC

Breast conditions
Condition

Gastrointerstinal conditions
UKMEC

Breast conditionsa) Undiagnosed breast symptoms

Condition

UKMEC

Gall bladder disease
I

C

3

2

a) Symptomatic(i) Treated by cholecystectomy2b) Benign breast conditions

1(ii) Medically treated3c) Family history of breast cancer

1(iii) Current

3d) Carriers of known gene mutations
associated with breast cancer (e.g.
BRCA1)3b) Asymptomatic

2

History of cholestasise) Breast cancer(i) Current breast cancer

4(ii) Past breast cancer

3a) Pregnancy related

2b) Past COC related

3

Viral hepatitisa) Acute or flare

Endocrine conditions
Condition

UKMEC

Diabetesa) History of gestational disease

I

C

3

2

b) Carrier

1c) Chronic

1

1

Cirrhosis*
1(i) Non-insulin dependent2a) Mild (compensated withoutcomplications)(ii) Insulin-dependent

2b) Severe (decompensated)

4c) Nephropathy/retinopathy/neuropathy

3

Liver tumoursd) Other vascular disease3a) Benignb) Non-vascular disease

Rheumatoid diseases
Condition

UKMEC

Systemic lupus erythematosus (SLE)2(ii) Hepatocellular adenoma

4b) Malignant (hepatoma)

4

C, continuation; I, initiation.

a) No antiphospholipid antibodies

2b) Positive antiphospholipid antibodies

4

Positive antiphospholipid antibodies

490(i) Focal nodular hyperplasia

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FSRH guideline: CHC

Questions for continuing professional development
The following multiple choice questions (MCQ) have only one correct answer and have beendeveloped for continuing professional development (CPD). The answers to the questions andinformation on claiming CPD points can be found in the ‘members-only section’ of the FSRH website(www.fsrh.org).
1. A woman taking lamotrigine is using the combined hormonal transdermal patch (CTP). Which oneof the following statements is correct?
a) Lamotrigine is a liver enzyme inducer and will reduce hormone levelsb) Serum lamotrigine levels can be reduced by CTPc) Lamotrigine levels are unchanged in the hormone-free interval (HFI)d) The benefits of using CTP with lamotrigine usually outweigh the risks
2. A woman attends clinic and is 3 days late restarting her combined oral contraception (COC) andhad unprotected sexual intercourse (UPSI) only on day 6 of her 7-day HFI having previously taken
her pills consistently and correctly. Which one of the following statements is incorrect?
a) She is at risk of pregnancyb) Copper intrauterine device (Cu-IUD) would not be first choice for emergency contraception
in this situation.
c) Ulipristal acetate (UPA) is a suitable choice of emergency contraception in this cased) If UPA is chosen, she needs to wait 120 hours before restarting her COC
3. Which one of the following statements about venous thromboembolic (VTE) risk with CHC iscorrect?
a) VTE risk when using CHC is lower than VTE risk during pregnancy/after deliveryb) Taking breaks from the pill is recommended as this reduces VTE riskc) VTE risk is higher with LNG- and norethisterone-containing COC compared to thosecontaining desogestreld) A thrombophilia screen is recommended before starting combined hormonal contraception(CHC)
4. A woman suffers from headache and nausea in the HFI. Which one of the following is an
inappropriate option to reduce symptoms?
a) Tricycle pill packetsb) Take pills continuouslyc) Flexible extended pill takingd) Increase estrogen dose to 35µg
5. Which one of the following conditions is not UKMEC 3 for CHC use?
a) Body mass index (BMI) ≥35 kg/m2b) Breast feeding and ≥6 weeks to < 6 months post-partumc) Age >35yrs and smoking < 15 cigarettes a dayd) Hypertension with systolic >140–159 mmHg or diastolic >90–99 mmHg
6. Regarding switching to CHC, which one of the following statements is incorrect?
a) 7 days of extra precautions are needed if CHC is started after taking desogestrel progestogenonly pills (POP) consistently and correctlyb) No extra precautions are needed if CHC is started on same day as in-date subdermal implantis removedc) 7 days of extra precautions are needed if CHC is started on the same day that an in-datelevonorgestrel-releasing intrauterine system (LNG-IUS) is removedd) Up to 9 days of extra precautions are required if an estradiol-containing COC is started andan in-date Cu-IUD is removed on day 3 of a menstrual cycle

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FSRH guideline: CHC

7. Which one of the following statements is incorrect regarding a woman who wants to switch from
CHC and is on day 6 of the HFI?
a) If she has a Cu-IUD inserted today, no additional precautions are neededb) If she is starts a POP today and has not had UPSI in the HFI, 2 days of additional precautions
are neededc) If she has a subdermal implant inserted today and has had UPSI in the HFI she should
restart her CHC for 7 daysd) If she has a LNG-IUS inserted today, and has not had UPSI in the HFI, no additional
precautions are required
8. Which one of the following statements is incorrect regarding cancer and CHC use?
a) Use of CHC is contraindicated for a woman whose mother had breast cancerb) Increased risk of breast cancer associated with CHC use declines to become non-significant
after 10 years of non-usec) Use of CHC for more than 5 years is associated with a small increase in the risk of cervicalcancerd) Use of CHC is associated with reduced risk of endometrial cancer and ovarian cancer
9. Which one of the following drugs does not alter the effectiveness of CHC?
a) St. John’s Wortb) Modafinilc) Sodium valproated) Topiramate
10. Which one of the following statements regarding CHC and migraine is correct?
a) CHC users with migraine with aura are at greater risk of haemorrhagic stroke than CHC
users without migraineb) Starting CHC for a woman who has pre-existing migraine without aura, is UKMEC 2c) If >5 years have elapsed since a woman’s last migraine with aura, benefits of CHC use
outweigh risksd) If a woman suffers from migraine without aura in the HFI, using an extended cycle regimen
will not be beneficial

Auditable outcomes
The following auditable outcomes have been suggested by the FSRH Clinical Standards Committee.
Auditable outcome

TargetWhat proportion of patients are informed about and given the choice of standard and tailored
regimens on commencing CHC

97%

What proportion of women have review of medical eligibility and have BP and BMI recorded
prior to prescription of CHC

100%

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Comments and feedback on published guideline
All comments on published this guideline can be sent directly to the Clinical Effectiveness Unit (CEU)of the Faculty of Sexual & Reproductive Healthcare (FSRH) via the FSRH website ( www.fsrh.org ).
The CEU may not respond individually to all feedback. However, the CEU will review all comments
and provide an anonymised summary of comments and responses, which are reviewed by theClinical Effectiveness Committee (CEC) and any necessary amendments made subsequently.
The Faculty of Sexual & Reproductive Healthcare (FSRH) is the largest UK professional membershiporganisation working in the field of sexual and reproductive health (SRH). We support healthcare
professionals to deliver high-quality healthcare including access to contraception. We provide our 15000 doctor and nurse members with NICE-accredited evidence-based clinical guidance, including
the UKMEC, the gold standard in safe contraceptive prescription, as well as clinical and service
standards.
The FSRH provides a range of qualifications and training courses in SRH, and we oversee theCommunity Sexual and Reproductive Healthcare (CSRH) Specialty Training Programme to train
consultant leaders in this field. We deliver SRH-focused conferences and events, provide memberswith clinical advice and publish BMJ Sexual & Reproductive Health – a leading international journal.
As a Faculty of the Royal College of Obstetricians and Gynaecologists (RCOG) in the UK, we workin close partnership with the College but are independently governed.
The FSRH provides an important voice for UK SRH professionals. We believe it is a human rightfor women and men to have access to the full range of contraceptive methods and SRH services
throughout their lives. To help to achieve this we also work to influence policy and public opinion
working with national and local governments, politicians, commissioners, policymakers, the media
and patient groups. Our goal is to promote and maintain high standards of professional practice in
SRH to realising our vision of holistic SRH care for all.
www.fsrh.org

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FSRH guideline: CHC

Correction notice
Since this guideline was published online the following changes have been made:February 2019 - Table 4; Estimated first year unintended pregnancy rates (% for perfect use ofprogestogen-only pill, progestogen-only injectable and levonorgestrel intrauterine device have beencorrected from 0.2, 0.6 and 0.6 to 0.3, 0.2 and 0.2, respectively.
July 2019 - Appendix 2; condition description for breast conditions e(i) Current and e(ii) Past andno evidence of current cancer for 5 years has been corrected to e(i) Current breast cancer ande(ii) Past breast cancer, respectively.
November 2020 - Table 2: additional guidance added for estradiol/nomegestrol combined oral
contraceptives; Box 2: additional link to specific advice; Section 12.5: added new bullet point todirect users to discuss health risks and specific advice for travel, altitude and surgery. Added
hyperlinks to relevant sections.
July 2023 - Table 3b and Table 7 has been updated.
October 2023 - Box 2 has been updated.

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