Clinical trial NCT03568851: Reproductive Health Outcomes by Method of Breast Milk Feeding
Official title: Reproductive Health Outcomes by Method of Breast Milk Feeding
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Breast Feeding
Milk Expression, Breast
Amenorrhea, Postpartum
Lead sponsor: University of California, Davis
Sponsor class: OTHER
First posted: 2018-06-26
Enrollment: 394
Sex: FEMALE
Minimum age (years): 15
Maximum age (years): 45
Standard ages: CHILD
ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Women who are planning on breastmilk feeding for at least 6 months after delivery of a singleton.

Brief summary: The purpose of this research is to determine whether there are differences in ovarian suppression between women who are feeding at the breast compared with women who are pumping.

* In the main study, the aim is to compare reproductive health outcomes, including amenorrhea rates, duration of lactation, and resumption of sexual activity, between mothers who are exclusively breastfeeding (i.e. feeding at the breast) and those who are pumping after a term or preterm delivery.
* In the sub-study, the aim is to determine the feasibility and acceptability of using urinary luteinizing hormone (LH) detection kits at home to detect ovulation in exclusively breastmilk feeding women.

Detailed description: Women will be recruited for this study during routine prenatal care. Interested and eligible participants will undergo an informed consent process. After, participants will answer questions regarding demographic information, medical history, obstetric and reproductive history, previous lactation history, and the Infant Feeding Intentions questionnaire.

Participants who are eligible after the second eligibility verification at the time of delivery hospitalization will be enrolled in the study. Enrolled participants will be given breastmilk and infant feeding logs to complete. Study staff will contact participants at 1, 2, 3, 4, 5, and 6 months after delivery to ask about breastmilk feeding practices in the last 24 hours, infant feeding, vaginal bleeding, sexual activity, use of contraceptive methods, and repeat pregnancies. In between the monthly phone calls, study staff will ask participants about the occurrence of vaginal bleeding.

For the sub-study, participants are recruited from the main study. Those who are eligible and interested will undergo an informed consent process. Participants will be given urinary LH detection kits and instructions for use at time of enrollment. Daily urine LH testing will start after 8 weeks postpartum. Participants will also receive monthly diaries to complete in addition to the breastmilk and infant feeding logs in the main study. Study staff will contact participants at 2, 3, 4, 5, and 6 months to review the diary information. If the urine LH test is positive, the participant will undergo a blood draw for serum progesterone levels to confirm ovulation.

The planned enrollment is 394 participants for the main study and 40 participants in the sub-study.

Eligibility criteria: MAIN STUDY

Inclusion Criteria:

* 15 through 45 years old
* planning to feeding her infant exclusively the mother's own milk for at least 6 months after delivery
* receiving prenatal care, plan to deliver, and plan to return to UC Davis for the postpartum visit
* 32 weeks gestation or greater at screening

Exclusion Criteria:

* have a multiple gestation pregnancy
* planning to initiate a hormonal contraceptive method at the postpartum visit

At time of delivery hospitalization, a second eligibility verification will occur and women will be excluded if they:

* initiated a hormonal contraceptive method (specifically intrauterine device, implant, depo provera injections) during the delivery hospitalization
* had a hysterectomy
* did not deliver at UC Davis
* are no longer interested in study participation

SUB-STUDY

Inclusion Criteria:

* enrolled in the main study
* within 8 weeks postpartum after delivering a singleton
* currently amenorrheic
* planning to continue breastmilk feeding for up to 6 months after delivery
* planning to avoid pregnancy in the first 6 months after delivery

Exclusion Criteria:

* less than 18 years old
* have a previous history of irregular or anovulatory cycles
* are using a hormonal method of contraception
* are unwilling to comply with study procedures

Primary outcomes:
measure: Proportion of women who are amenorrheic
timeFrame: 6 months postpartum
measure: Proportion of ovulation detected, as measured by serum progesterone levels greater than or equal to 3 ng/mL, in women with a positive urine luteinizing hormone test
timeFrame: 6 months postpartum
measure: Proportion of women who would use the urine luteinizing hormone tests again
timeFrame: 6 months postpartum
Secondary outcomes:
measure: Duration of lactation
timeFrame: within 6 months
measure: Time to resumption of sexual activity
timeFrame: within 6 months
measure: Duration of amenorrhea
timeFrame: within 6 months
measure: Time to initiation of another contraceptive method
timeFrame: within 6 months
measure: Proportion of women who meet criteria for lactational amenorrhea method
timeFrame: at 6 months postpartum
measure: Preliminary estimates of contraceptive efficacy of LAM
timeFrame: within 6 months postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 1 postpartum
timeFrame: 1 month postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 2 postpartum
timeFrame: 2 months postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 3 postpartum
timeFrame: 3 months postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 4 postpartum
timeFrame: 4 months postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 5 postpartum
timeFrame: 5 months postpartum
measure: Proportion of women feeding at breast, expressing milk, or both at month 6 postpartum
timeFrame: 6 months postpartum
measure: Time to ovulation by method of breastmilk feeding (i.e. primarily breastfeeding or primarily pumping)
timeFrame: within 6 months postpartum
Other outcomes:
Locations:
city: Sacramento
country: United States
facility: University of California, Davis
state: California
Study officials:
affiliation: UC Davis
name: Melissa Chen, MD
role: PRINCIPAL_INVESTIGATOR
References: