Hormones and Menopause

Tips from the National Institute on Aging

National Institute on Aging

National Institutes of health

U.S. Department of Health and Human Services

Waking up flushed and sweaty several times a 

night left Cathy feeling tired all day. But when 

she began to feel hot on and off during the 

day as well, she went to see Dr. Kent. He told 

Cathy she was having hot flashes—a sign that 

she was starting the menopause transition. 

Dr. Kent talked about several ways to control 

her hot flashes. One was to use the hormone 

estrogen for a short time. He talked about 

the benefits and risks of this choice. Cathy 

said she remembered hearing something on a 

TV talk show about using hormones around 

menopause. Were they helpful? Were they 

safe? She didn’t know.

A hormone is a chemical substance made 

by an organ like the thyroid gland or ovary. 

Hormones control different body functions. 

Examples of hormones are estrogen, progesterone, testosterone, and thyroid hormone.

In a woman’s body during the menopause 

transition, the months or years right before 

menopause (her final menstrual period), levels 

of several hormones, including estrogen and 

progesterone, go up and down irregularly. 

This happens as the ovaries work to keep up 

with the needs of the changing body. 

Menopause is a normal part of aging. It 

is not a disease or disorder that has to be 

treated in all cases. Women may decide to 

use hormones like estrogen because of the 

benefits, but there are also side effects and 

risks to consider. 

Dr. Kent told Cathy to call back for a prescription if she decided to try using hormones 

to relieve her symptoms. She read pamphlets 

from the doctor’s office and talked to her 

friends. Lily, who had surgery to remove her 

uterus and ovaries, has been taking the 

hormone estrogen since the operation. Sandy 

said she’s had a few hot flashes but isn’t 

really uncomfortable enough to take hormones. 

Melissa is bothered by hot flashes and can’t 

sleep, but her doctor thinks she should not use 

estrogen because her younger sister has breast 

cancer. Each friend had a different story. Cathy 

wanted more information.

Do hormones relieve menopause 

symptoms?

Symptoms such as hot flashes might result 

from the changing hormone levels during 

the menopause transition. After a woman’s 

last menstrual period, when her ovaries 

make much less estrogen and progesterone, 

some symptoms of menopause might 

disappear, but others may continue.
HORMONES AND MENOPAUSE

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To help relieve these symptoms, some 

women use hormones. This is called 

menopausal hormone therapy (MHT). 

This approach used to be called hormone 

replacement therapy or HRT. MHT is a 

more current, umbrella term that describes 

several different hormone combinations 

available in a variety of forms and doses.

How would I use MHT?

Estrogen is a hormone used to relieve the 

symptoms of menopause. Estrogen alone (E) 

may be used by a woman whose uterus has 

been removed. But a woman who still has a 

uterus must add progesterone or a progestin 

(synthetic progesterone) along with the 

estrogen (E+P). This combination lowers 

the chance of an unwanted thickening of 

the lining of the uterus and reduces the risk 

of cancer of the uterus, an uncommon, but 

possible result of using estrogen alone.

Cathy’s friend Stephanie takes a pill 

containing estrogen and progestin, but 

Cathy has trouble swallowing pills. If MHT 

is only available as a pill, that is something 

she’d consider when making her decision.

Estrogen comes in many forms. Cathy 

could use a skin patch, vaginal tablet, or 

cream; take a pill; or get an implant, shot, 

or vaginal ring insert. She could even apply 

a gel or spray. There are also different 

types of estrogen (such as estradiol and 

conjugated estrogens). Estradiol is the most 

important type of estrogen in a woman’s 

body before menopause. Other hormones, 

progesterone or progestin, can be taken 

as a pill, sometimes in the same pill as the 

estrogen, as well as a patch (combined with 

estrogen), shot, IUD (intrauterine device), 

gel, or vaginal suppository.

The form of MHT your doctor suggests may 

depend on your symptoms. For example, 

an estrogen patch (also called transdermal 

estrogen) or pill (oral estrogen) can relieve 

hot flashes, night sweats (hot flashes that 

bother you at night), and vaginal dryness. 

Other forms—vaginal creams, tablets, or 

rings—are used mostly for vaginal dryness 

alone. The vaginal ring insert might also 

help some urinary tract symptoms. 

The dose can also vary, as can the timing 

of those doses. Some doctors suggest that 

estrogen be used every day, but that the progesterone or progestin be used cyclically—

for 10 to 14 straight days every 4 weeks. A 

cyclic schedule is thought to mimic how 

the body makes estrogen and progesterone 

before menopause. This approach can cause 

some spotting or bleeding, like a light 

period, which might get lighter or go away 

in time. Alternatively, some women take 

estrogen and progesterone or progestin 

continuously—every day of the month. 

Is there a downside to taking 

hormones?

A lot of the information Cathy read said that 

taking estrogen is the most effective way to 

relieve hot flashes, night sweats, and vaginal 

dryness. Estrogen also helps keep bones strong. 

Cathy thought that those seemed like good 

reasons to use MHT. But she wondered, is 

there a downside?

Research has found that, for some women, 

there are serious risks, including an increased chance of heart disease, stroke, 

blood clots, and breast cancer, when using 

MHT. There may also be an increased risk 

of dementia in women when they start MHT 

after age 65. These concerns are why every 
Tips from the National Institute on AginG

3

woman needs to think a lot before deciding 

to use menopausal hormone therapy.

Also, some women develop noticeable side 

effects from using hormones:

z breast tenderness

z spotting or a return of monthly periods

z cramping

z bloating

By changing the type or amount of the 

hormones, the way they are taken, or the 

timing of the doses, your doctor may be able 

to help control these side effects. Or, over 

time, they may go away on their own.

What more should I know about 

the benefits and risks of hormones?

Cathy knows there have been news stories 

about menopausal hormone therapy research 

findings. But, several years ago, when she first 

heard about the risks of using estrogen, she 

didn’t really pay attention. Now she wants 

to know more about the risks.

Over the years, research findings have led to 

a variety of positive, negative, and sometimes 

conflicting reports about menopausal 

hormone therapy. Some of these findings 

came from randomized clinical trials, 

the most convincing type of research. 

Historically, clinical trials often used one 

type of estrogen called conjugated estrogens. 

Several other types of estrogen, as well as 

progesterone and progestins, have also 

been tested in small trials to see if they have 

an effect on heart disease, breast cancer, 

or dementia.

Let’s look more closely at what we have 

learned from these small studies.

Hot flashes and night sweats—Estrogen 

will relieve most women’s hot flashes and 

night sweats. If you stop using estrogen, you 

may again start having hot flashes. Lifestyle 

changes and certain prescription medicines 

also might help some women with hot 

flashes. For most women, hot flashes and 

night sweats go away in time. 

Vaginal dryness—Estrogen improves 

vaginal dryness, probably for as long as you 

continue to use it. If vaginal dryness is your 

only symptom, your doctor might prescribe 

a vaginal estrogen. A water-based lubricant, 

but not petroleum jelly, may also relieve 

vaginal discomfort.

Cholesterol levels—Estrogen improves 

cholesterol levels, lowering LDLs (the “bad” 

kind of cholesterol) and raising HDLs (the 

“good” kind of cholesterol). The pill form of 

estrogen can cause the level of triglycerides 

(a type of fat in the blood) to go up. The 

estrogen patch does not seem to have this 

effect, but it also does not improve cholesterol to the same degree as the pill form. But, 

improving cholesterol levels is not a reason 

to take estrogen. Other medicines and lifestyle changes will improve cholesterol levels 

more effectively.

What is the Women’s Health 

Initiative? What have we learned 

from it?

Before menopause, women generally have 

a lower risk of heart disease than men. 

This led experts to wonder whether giving 

women estrogen after menopause might 

help prevent heart disease. In 1992, the 

National Institutes of Health (NIH), the 

nation’s premier medical research agency, 

began the Women’s Health Initiative (WHI) 

to explore ways postmenopausal women 
HORMONES AND MENOPAUSE

4

might prevent heart disease, as well as 

osteoporosis and cancer. One part of the 

WHI, the Hormone Trial, looked at oral 

conjugated estrogens used alone (E) or 

with a particular progestin (E+P) to see if, 

in postmenopausal women, estrogen could 

prevent heart disease without increasing the 

chance of breast cancer. 

In July 2002, the E+P part of the WHI 

Hormone Trial was stopped early because it 

became clear to the researchers that the overall risk of taking E+P outweighed the benefits: 

Benefits

z Fewer fractures

z Less chance of colon and rectum cancer

Risks

z More strokes

z More serious blood clots

z More heart attacks

z More breast cancers

In April 2004, the rest of the Hormone Trial, 

the E alone group, was also halted because 

using estrogen alone did not have a positive 

effect on heart disease overall and increased 

the risk of stroke. 

During the first 3 years after stopping the E+P 

used in the WHI, women were no longer at 

greater risk of heart disease, stroke, or serious 

blood clots than women who had not used 

MHT. On the other hand, they also no longer 

had greater protection from fractures. The 

women still had an increased risk of breast 

cancer, but their risk was smaller than it was 

while they were using hormones.

It appears from the WHI that women over 

age 60 should not begin using MHT to 

protect their health—it will not prevent 

heart disease or dementia when started 

several years after menopause. In fact, older 

women in the study using MHT were at 

increased risk of certain diseases. On the 

other hand, women who were younger than 

age 60 did not appear to be at increased risk 

of heart disease, and the overall risks and 

benefits appeared to be balanced. 

It is important to remember that the WHI 

findings are based on the specific oral form 

(rather than patch, gel, etc.), dose, and type 

of estrogen and progestin studied in the 

WHI. Which hormones and dose you use 

and the way you take them might change 

these benefits and risks. We don’t know 

how the WHI findings apply to these other 

types, forms, and doses of estrogen and 

progesterone or progestin. 

What are some other options?

Cathy is like a lot of women bothered by 

symptoms of menopause. After learning 

about some research results, she is concerned 

about using menopausal hormone therapy 

for relief of her symptoms. But it’s been several

years since some study findings raised concerns, 

and now Cathy is wondering whether there 

is anything new. 

Women now have more options than when 

the WHI study was first planned. More 

The U.S. Food and Drug Administration (FDA) 

now recommends that women with moderate 

to severe menopausal symptoms who want to 

try menopausal hormone therapy for relief use 

it for the shortest time needed and at the lowest 

effective dose. 
Tips from the National Institute on AginG

5

types of estrogens are available, and some 

of them come in a variety of forms. For 

example, synthetic estradiol, now available 

in several forms (pill, patch, cream, gel, 

etc.), is chemically identical to the estrogen 

most active in women’s bodies before 

menopause. If it is not taken by mouth, but 

rather applied to the skin or taken as a shot, 

estradiol appears to work the same way as 

estradiol made in the body. Investigators 

are now studying a low-dose estradiol patch 

(transdermal estradiol) compared to a lowdose conjugated estrogens pill to see whether 

one or both slow hardening of the arteries 

in women around the age of menopause and 

whether the estradiol patch is as effective 

and, perhaps, safer than the conjugated 

estrogens pill. These alternatives are creating 

more choices for women seeking relief from 

their menopausal symptoms, as well as a 

variety of new opportunities for research.

Besides a pill, some estrogens come in 

different and sometimes new forms—skin 

patch, gel, emulsion, spray, and vaginal 

ring, cream, and tablet. These forms work 

in the body somewhat differently than a pill 

by entering your body directly through the 

skin or walls of the vagina. Oral estrogen 

(a pill) is chemically changed in the liver. 

Some studies suggest that if estrogen enters 

through the skin and bypasses the liver, the 

risk of serious blood clots or stroke might 

be lower. Others suggest a lower risk of 

gallbladder disease. This may also allow a 

change in dosage—further testing may show 

that the same benefits might come from 

lower doses than are needed with a pill.

What questions remain 

unanswered?

Cathy was beginning to understand more 

about the benefits and risks of using hormones, 

but she wondered whether there are still 

questions about the WHI results and menopausal hormone therapy in general. What 

else needs to be looked at?

Experts now know more about menopause 

and have a better understanding of what 

the WHI results mean. But, they have new 

questions also. 

z The average age of women participating 

in the trial was 63, more than 10 years 

older than the average age of menopause, 

and the WHI was looking at reducing 

the risk of chronic diseases of growing 

older like heart disease and osteoporosis. 

Do the WHI results apply to younger 

women choosing MHT to relieve symptoms around the time of menopause or 

to women who have early surgical menopause (surgery to remove both ovaries or 

the uterus)?

z Other studies show that lower doses of 

estrogen than were studied in the WHI 

provide relief from symptoms of menopause for some women and still help 

women maintain bone density. What are 

the long-term benefits and risks of lower 

doses of estrogen?

z In the WHI, women using E alone did 

not seem to have a greater risk of heart 

disease than women not using hormones. 

Does this mean that the risk of heart 

disease in healthy women in their 50s 

who can use estrogen alone might not be 

higher than the risk in women who don’t 

use estrogen? 

z Would using progesterone or a different 

progestin than the one used in the WHI 

be less risky to a woman’s heart? 

z The combination menopausal hormone 

therapy used in the WHI makes it somewhat more likely that a woman could 
HORMONES AND MENOPAUSE

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develop breast cancer, especially with 

long-term use. Is using a different type of 

estrogen, a smaller dose of estrogen or progesterone, or a different progestin (instead 

of medroxyprogesterone acetate) safer?

z Does using estrogen around the time of 

menopause change the risk of possible dementia in later life as starting it after age 65 

did in the WHI Memory Study (WHIMS)?

The National Institute on Aging and other 

parts of the National Institutes of Health, 

along with other medical research centers, 

continue to explore questions such as these. 

They hope that in the future these studies 

will give women additional facts needed to 

make informed decisions about relieving 

menopausal symptoms.

What are “natural hormones”?

Cathy’s friend Susan thinks she is not at risk for 

serious side effects from menopausal hormone 

therapy because she uses “natural hormones” 

to treat her hot flashes and night sweats. Cathy 

asked Dr. Kent about them. He told her that 

there is very little reliable scientific information 

from high-quality clinical trials about the safety 

of “natural” or compounded hormones, how 

well they control the symptoms of menopause, 

and whether they are as good or better to use 

than FDA-approved estrogens, progesterone, 

and progestins.

The “natural hormones” Susan uses are 

estrogen and progesterone made from plants 

such as soy or yams. Some people also call 

them bioidentical hormones because they 

are supposed to be chemically the same as 

the hormones naturally made by a woman’s 

body. These so-called natural hormones 

are put together (compounded) by a compounding pharmacist. This pharmacist 

follows a formula decided on by a doctor 

familiar with this approach. Compounded 

hormones are not regulated or approved by 

the FDA. So, we don’t know much about 

how safe or effective they are or how the 

quality varies from batch to batch. 

Drug companies also make estrogens and 

progesterone from plants like soy and yams. 

Some of these are also chemically identical 

to the hormones made by your body. These

other forms of MHT are available by prescription. Importantly, hormones made by 

drug companies are regulated and approved 

by the FDA.

There are also “natural” treatments for the 

symptoms of menopause that are available 

over-the-counter, without a prescription. 

Black cohosh is one that women use, but 

a couple of clinical trials have shown that 

it did not relieve hot flashes in postmenopausal women or those approaching menopause. Because of rare reports of serious liver 

disease, scientists are concerned about the 

possible effects of black cohosh on the liver. 

Other “natural” treatments are made from 

soy or yams. None of these are regulated or 

approved by the FDA.

What’s right for me? 

There is no single answer for all women 

who are trying to decide whether to use 

menopausal hormone therapy (MHT). You 

have to look at your own needs and weigh 

your own risks.

Here are some questions you can ask 

yourself and talk to your doctor about:

z Do menopausal symptoms such as hot 

flashes or vaginal dryness bother me a lot? 

Like many women, your hot flashes or 

night sweats will likely go away over time, 
Tips from the National Institute on AginG

7

but vaginal dryness may not. MHT can 

help with troubling symptoms.

z Am I at risk for developing osteoporosis? 

Estrogen might protect bone mass while 

you use it. However, there are other drugs 

that can protect your bones without MHT’s 

risks. Talk to your doctor about the risks 

and benefits of those medicines for you.

z Do I have a history of heart disease or risk 

factors such as high blood cholesterol? 

Using estrogen and progestin can increase 

your risk.

z Do I have a family history of breast cancer?

If you have a family history of breast 

cancer, check with your doctor about 

your risk.

z I have high levels of triglycerides and a family history of gallbladder disease. Can I use 

MHT? The safety of any kind of MHT in 

women with high levels of triglycerides or 

a family history of gallbladder disease is 

not known. But some experts think that 

using a patch will not raise your triglyceride level or increase your chance of gallbladder problems. Using an oral estrogen 

pill might.

z Do I have liver disease or a history of stroke 

or blood clots in my veins? MHT, especially 

taken by mouth, might not be safe for you 

to use.

In all cases, talk to your doctor about how 

best to treat or prevent your menopause 

symptoms or diseases for which you are 

at risk. 

If you are already using menopausal 

hormone therapy and think you would 

like to stop, first ask your doctor how to 

do that. Some doctors suggest tapering 

off slowly.

Whatever decision you make now about 

using MHT is not final. You can start or 

end the treatment at any time, although, 

as we learned from the WHI, it appears that 

it is best not to start MHT many years after 

menopause. If you stop, some of your risks 

will lessen over time, but so will the benefits. 

Discuss your decision about menopausal 

hormone therapy with your doctor at your 

annual checkup.

MHT is not one size fits all

Cathy realized that talking to her friends 

about what each is doing to relieve menopause symptoms was helpful, but that her 

decision needed to be just for her. And she 

was sure that basing her decision just on 

what she heard on a TV show might not 

be the best way to choose. She tried to find 

sources of information that seemed to be 

unbiased and didn’t have a product to 

promote. She felt most comfortable with 

science-based websites like the National 

Institutes of Health, the U.S. Food and Drug 

Administration, or doctors’ professional 

groups.

Each woman is different, and the decision 

for each one about menopausal hormone 

therapy will probably also be different. 

But, almost every research study helps give 

women and their doctors more information 

to answer the question: Is menopausal 

hormone therapy right for me?
HORMONES AND MENOPAUSE

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N IH PUB LI CAT I ON NO. 09-7482

SEPTEMBER 2009

For more information on health and aging, including menopause, contact:

National Institute on Aging Information Center

P.O. Box 8057

Gaithersburg, MD 20898-8057

1-800-222-2225 (toll-free)

1-800-222-4225 (TTY/toll-free)

www.nia.nih.gov

www.nia.nih.gov/Español

For More Information

Other resources on menopausal hormone 

therapy include:

National Institutes of Health

Menopausal Hormone Therapy

Information

www.nih.gov/PHTindex.htm

National Library of Medicine

MedlinePlus

www.medlineplus.gov

This National Library of Medicine website 

has information on many health subjects, 

including menopause. Click on Health 

Topics. Choose any topic you are interested 

in, such as menopause, menopausal hormone 

therapy, or osteoporosis, by clicking on the 

first letter of the topics and scrolling down 

the list to find it.

American College of Obstetricians 

and Gynecologists

409 12th Street, SW

Box 96920

Washington, DC 20090-6920

1-202-638-5577

www.acog.org

Food and Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993-0002

1-888-463-6332 (toll-free)

North American Menopause 

Society

P.O. Box 94527

Cleveland, OH 44101

1-440-442-7550

1-800-774-5342 (toll-free)

www.menopause.org