Over the past decades, menopausal women have been encouraged to use hormone replacement therapy (HRT) for its apparent health- and youth-preserving benefits. It is true that HRT lowers the risk of osteoporosis and possibly colon cancer.^{1, 2} But, compared to women not taking hormones, women taking HRT have slightly higher rates of breast cancer, ovarian cancer, heart attack, stroke, blood clots, and Alzheimer's disease as well as other forms of dementia.^{2, 3, 4}

Although HRT risks are not high for most women, on average, the small risks outweigh the small benefits. As a result, women's health experts now recommend that, for most women, HRT use should be limited to one or both of the following:

• Short-term menopausal symptom relief.
• Severe osteoporosis risk (when nonhormonal treatments have been considered and/or tried first).

Experts disagree about using HRT as a first choice for menopausal symptoms and osteoporosis prevention after menopause.^{5, 6}

Consider the following when deciding whether to start or continue taking hormone replacement therapy (HRT):

• The risks of short-term HRT use are small but significant, particularly for women with preexisting risk factors:^{7, 2}
  • After 1 year's use, HRT causes changes on mammograms in 40 per 1,000 women. These changes aren't diagnosed as cancer but require further testing.³
  • After 5 years' use, HRT causes 4 to 6 breast cancers per 1,000 women. This risk increases with prolonged HRT use.^{2, 7}
  • The risk of blood clots in the legs or lungs is greatest during the first 2 years, affecting about 6 per 1,000 women.
• Heart disease is the number one killer of women, and HRT use causes heart disease in a small number of women.^{8, 9}
• Heart risk from HRT does not seem to affect women in their first 10 years after menopause.^{10, 11} Review your personal heart risk profile versus possible HRT benefits as part of your treatment decision process.
• For perimenopausal symptoms, consider non-HRT treatments, including breathing-for-relaxation exercises; certain antidepressants, low blood pressure medications, and black cohosh for hot flashes; and vaginal lubricant or vaginal estrogen (cream, ring, or tablet) for dryness and irritation.¹²
• If you decide to use HRT for symptom relief, use the lowest effective dose for the shortest possible time, and see your health professional regularly to reevaluate your personal benefits and risks.
• HRT helps prevent bone loss and osteoporosis. If you are at high risk for osteoporosis, HRT is one of several treatments you can consider.

What is menopause?

After several years of fluctuating hormone levels and irregular menstruation in your 40s or 50s, your estrogen and progesterone levels begin to decline. After 6 months to 1 year of decline, your estrogen level drops past a certain point, and your menstrual cycle ends. Menopause is the point in time when you've had no menstrual periods for 1 year.

During the first year or so after menopause (postmenopause), estrogen levels continue to decline, which can cause or worsen perimenopausal symptoms like hot flashes and insomnia. Once your hormone levels reach a stable low point, these symptoms are likely to subside; this typically takes 1 to 2 years. Some women, however, continue with symptoms for years, perhaps because their estrogen levels are lower than average.

Low estrogen is part of the healthy, natural state of the postmenopausal phase of life-it is tailored to the way your body is meant to function after your childbearing years. Low estrogen is good for you in the sense that it lowers your hormone-related cancer risk. However, because estrogen also plays an important role in skin and bone health, low estrogen creates some health concerns for the postmenopausal woman.

• Following years of gradual decline in bone density and strength, low estrogen after menopause speeds up bone loss, increasing your risk of osteoporosis.
• Low estrogen leads to low collagen, a building block of skin and connective tissue. As a result, the vaginal lining and the lower urinary tract also thin and weaken. This condition, called genitourinary atrophy, can make sexual relations difficult and can increase the risk of vaginal and urinary tract infection.

What other treatments are available for perimenopausal symptoms?

Although the perimenopausal transition itself is a natural body change that doesn't require treatment, severe symptoms can disrupt a woman's life and sense of well-being. The first and best approach to reducing your perimenopausal symptoms (and long-term health risks related to aging) is to lead a healthy lifestyle-avoid excess caffeine, alcohol, and stress; eat well; and exercise regularly.

If you need additional relief, you have several non-HRT treatment options to choose from. Slow, rhythmic breathing exercises are a proven way to manage hot flashes and emotional symptoms.^{13, 14} Vaginal lubricants (such as Astroglide or K-Y Jelly) are useful for vaginal dryness, and vaginal estrogen (cream, ring, or tablet) can help with vaginal dryness and irritation. Certain types of antidepressants (SSRIs) or blood pressure medication (clonidine) can reduce hot flashes, and black cohosh can help with hot flashes and other hormone-related symptoms.

Before menopause, you can also consider low-dose estrogen-progestin birth control pills for perimenopausal symptoms and pregnancy prevention, as long as you have no risk factors for heart disease or breast cancer and you do not smoke.

What is hormone replacement therapy?

Estrogen replacement therapy (ERT) refers to the daily use of estrogen to increase a woman's hormones to premenopausal levels. Women with a uterus who take estrogen also need the hormone progestin to prevent the estrogen from affecting the uterine lining (endometrium), which can lead to endometrial cancer. The combination of estrogen and progestin is called hormone replacement therapy (HRT). Women with a uterus take HRT; those who have had a hysterectomy to remove the uterus take ERT.

The U.S. Food and Drug Administration (FDA) has updated its HRT recommendations and now only approves estrogen-progestin HRT for:

• Short-term treatment of perimenopausal symptoms. Women who do decide that HRT benefits outweigh their risks are advised to use the lowest effective dose for as short a time as possible, not exceeding 3 or 4 years.
• Osteoporosis prevention and treatment, in select, severe cases. Most experts recommend that HRT only be considered for women with significant risk of osteoporosis that outweighs their risks from taking HRT.¹⁵ Women are now encouraged to consider all possible osteoporosis treatments and to compare their risks and benefits.¹⁶ For more information, see the topic Osteoporosis.

The FDA is reviewing its ERT recommendations, based on March 2004 stroke risk information from the Women's Health Initiative ERT study.¹⁷ Other low-dose ERT research is currently in progress.

What are the benefits of taking estrogen?

When taken as ERT or HRT, estrogen:^{2, 1}

• Helps prevent osteoporosis after menopause by slowing bone loss and promoting some increase in bone density.¹
• Reduces hot flashes and sleep problems in most, but not all, women.¹
• Maintains the lining of the vagina, reducing irritation.
• Maintains skin collagen levels, which decline as estrogen levels decline. Collagen is responsible for the stretch in skin and muscle.
• Increases the amount of HDL ("good") cholesterol and decreases the amount of LDL ("bad") cholesterol in the blood.
• Reduces the risk of dental problems, such as tooth loss and gum disease.
• May reduce the risk of colon cancer.²

What are the risks of hormone replacement therapy?

HRT increases the risks of breast cancer, ovarian cancer, blood clots, heart disease, stroke, and dementia. Estrogen alone (ERT) is also linked to increased stroke, ovarian cancer, and possible breast cancer risk.^{18, 7, 19} No particular form or dosage of ERT or HRT has been proven safer than another.⁵

Among the women using HRT in the recent Women's Health Initiative trials, most did not develop major health problems. But after the first 1 to 4 years of using HRT, a small yet significant number of women did develop signs of cancer, blood clots, heart disease, stroke, and dementia.^{2, 3, 4}

• Within the first 2 years, HRT use slightly increased the risk of blood clots in the lungs (pulmonary embolism) and legs (deep vein thrombosis) in all healthy postmenopausal women regardless of risk factors.²⁰
• During the second year, HRT use began to slightly increase heart attack and stroke risk in all healthy postmenopausal women, regardless of risk factors. Early signs of heart disease first became apparent during the first year of use.^{20, 9} Heart disease risk does not increase for women in the first 10 years after menopause.^{21, 10, 11}
• After 1 year, HRT use increased the number of abnormal mammograms by approximately 4% per year. Daily estrogen-progestin increased breast density compared with estrogen alone or placebo. Although the abnormal mammograms required additional medical evaluation, they were not linked to an early increase in breast cancer. Studies are ongoing to learn more about breast density change from HRT.³
• After 4 years of use, HRT-related breast cancers first became apparent. The number of HRT-related breast cancers increased with each additional year of HRT use. Women taking HRT generally had larger, more advanced tumors than women who developed breast cancer while taking a placebo treatment.² (Some of these cancers, however, may respond more favorably to treatment.)²²
• After 4 years, HRT use slightly increased the incidence of Alzheimer’s disease and other dementias in women ages 65 and older. HRT does not provide protection from dementia or cognitive impairment, as was previously believed.⁴ (Most of the women in this study started HRT several years after menopause, when Alzheimer's risk naturally increases. Therefore, experts do not yet know whether the effect of HRT on Alzheimer's risk is the same for younger women who use short-term HRT starting at menopause.)

Serious health events caused or prevented by HRT, per 1,000 women (estrogen 0.625 mg plus progestin 2.5 mg) ^{2, 6}

Health event	After 2 years of HRT use	After 5.2 years of HRT use
Blood clots (venous thromboembolism)	6 more*	9 more
Coronary artery disease	3 more **	4 more
Breast cancer	No change***	4 more
Stroke	1 more****	4 more
Colorectal cancer	No change	3 fewer#
Hip fractures	1 fewer	2 fewer
Death	No change	No change
* Risk is greatest during the first 2 years of use. ** Signs develop as early as the first year of use. *** First noted after 4 years of use. **** First noted after 1 year of use. # Benefit appears after 3 years of use.

Your risks. It is impossible to know whether you will develop health problems from HRT. If you have no personal or family history of breast cancer, ovarian cancer, heart attack, stroke, blood clots, and dementia, your increased HRT risks are likely to be small. If you have a personal or family history of breast cancer, ovarian cancer, or heart disease, your HRT risks are likely to be higher than average, making the risks outweigh the benefits. If you have had breast cancer, which can be triggered or worsened by estrogen, taking HRT is not safe for you.

Low-dose HRT. The typical HRT dose is 0.625mg of estrogen plus 2.5mg of progestin. In March 2003, the FDA approved a low-dose version of Prempro, containing 0.3mg of estrogen and 1.5mg of progestin. This low-dose version may help hot flashes and bone density and is hoped to reduce the risks related to higher-dose HRT, but it needs more study.

Low-dose estrogen for osteoporosis. Researchers are studying the effects of low-dose estrogen therapy. A small early study has shown that a low estrogen dose-0.25mg per day-may keep the bones as strong as the higher dose.²³ However, the long-term risks of taking low-dose estrogen are not yet known.

How and when do I stop taking hormone replacement therapy?

There is no way of knowing in advance whether you will have perimenopausal symptoms when you stop using HRT (or ERT). While some women have no symptoms, others are mildly affected, and some have moderate to severe symptoms. Most women find that their symptoms subside over time.

How to stop HRT. There are currently no evidence-based guidelines for stopping HRT. While some women have stopped all at once, many health professionals suggest gradually cutting back your dose or increasing the time between doses over several weeks or months (tapering). It makes sense that tapering might prevent perimenopausal symptoms related to a sudden drop in estrogen. You can taper by reducing your daily dose, increasing the time between dosages, or trimming back an estrogen patch over time. If you do develop symptoms when tapering HRT, consider all other treatment options with your health professional, including waiting awhile to see whether your symptoms naturally subside.

When to stop HRT. Ultimately, it is up to you and your health professional to decide how long to take HRT. After weighing the risks, some women will continue to take HRT for years to come, while others stop as soon as they learn of the risks. If you have been taking HRT for many years, talk to your health professional about stopping HRT.

There are currently no evidence-based guidelines for when to stop short-term HRT. ⁵ But based on the risks, HRT use for 4 or more years is considered "long term."

If you develop symptoms when tapering or suddenly stopping HRT, consider how severe your symptoms are, what other treatment options are available for symptom relief, and how long you've been taking HRT. You can:

• Slightly increase your HRT dose until symptoms subside. After another 6 months to 1 year, try to taper off again.
• Continue with your plan to stop HRT and see whether symptoms subside over a few months.
• Continue with your plan to stop HRT and try another type of treatment.

If you need more information, see the topic Menopause and Perimenopause.

If you have decided that you are in need of symptom treatment after menopause or that you need to treat or prevent osteoporosis, your choices are:

• Use another treatment for perimenopausal symptoms or osteoporosis prevention.
• Use low-dose hormone replacement therapy for the shortest time possible.

The decision about whether to take hormone replacement therapy takes into account your personal feelings and the medical facts.

Making a decision about HRT

Reasons to take HRT

Reasons to not take HRT

Low-dose, short-term HRT (up to 4 or 5 years). You have no risk factors for heart disease, blood clots, stroke, or breast or ovarian cancer, are willing to accept the small increase in risks of cancer and heart disease, and you: Have considered or tried other treatments. Have moderate to severe perimenopausal symptoms that are disrupting your sleep and/or daily life. Long-term HRT. You are willing to accept the breast and ovarian cancer, blood clot, heart disease, and possible dementia risks of continuing HRT for longer than 4 or 5 years, and you: Are at high risk for osteoporosis and have considered or tried other osteoporosis therapies. Have long-standing perimenopausal symptoms (such as hot flashes) that only HRT will relieve. Are there other reasons you might want to take hormone replacement therapy?

You have not considered or tried other treatment options. You are concerned about blood clot and stroke risk. You are 10 or more years past menopause and are concerned about heart disease risk. You have been taking HRT for longer than 4 or 5 years and are concerned about increased cancer and dementia risks. (An HRT-related increase in dementia has been observed in women older than 65. The risk of later dementia and heart disease in women taking HRT in their 50s is not known.)5 You only have vaginal or urinary tract symptoms, which can be treated with vaginal estrogen (cream, ring, or tablet). You need a preventive treatment for heart disease or stroke (HRT does not prevent these conditions). Do not use HRT if you have:5, 24 A personal history of breast cancer, ovarian cancer, or endometrial cancer. A personal history of pulmonary embolism, deep vein thrombosis, heart attack, or stroke. (Your risks may also be higher if you have a family history of these conditions.) Vaginal bleeding from an unknown cause. Active liver disease (oral estrogen stresses the liver; an estrogen patch or cream does not). Are there other reasons you might not want to take hormone replacement therapy?

These personal stories about deciding whether to take HRT may help you make your decision.

Use this worksheet to help you make your decision. After completing it, you should have a better idea of how you feel about hormone replacement therapy (HRT). Discuss the worksheet with your doctor.

Circle the answer that best applies to you.

I have tried other perimenopausal treatment options.	Yes	No	Unsure
I have not yet reached menopause and can also consider low-dose birth control pills.	Yes	No	Unsure
I am in my 50s and consider my cancer, heart disease, and dementia risks to be low.	Yes	No	Unsure
I have a high osteoporosis risk.	Yes	No	Unsure
I have a personal or family history of heart attack, stroke, blood clots in the lungs or legs, or breast or ovarian cancer.	Yes	No	Unsure
I have unbearable perimenopausal symptoms that other therapies cannot control.	Yes	No	Unsure
I think I would take HRT for as long as I need relief from bothersome symptoms.	Yes	No	Unsure
I have been taking HRT for more than 5 years.	Yes	No	Unsure
I would consider taking HRT, but only for a short period of time.	Yes	No	Unsure

Use the following space to list any other important concerns you have about this decision.

What is your overall impression?

Your answers in the above worksheet are meant to give you a general idea of where you stand on this decision. You may have one overriding reason to use or not use hormone replacement therapy.

Check the box below that represents your overall impression about your decision.

Leaning toward taking hormone replacement therapy

Leaning toward NOT taking hormone replacement therapy

Citations

1. Speroff L, Fritz MA (2005). Menopause and the perimenopausal transition. In Clinical Gynecologic Endocrinology and Infertility, 7th ed., pp. 621–688. Philadelphia: Lippincott Williams and Wilkins.

2. Rossouw JE, et al. (2002). Risks and benefits of estrogen plus progestin in healthy postmenopausal women. Principal results from the Women's Health Initiative randomized controlled trial. JAMA, 288(3): 321–333.

3. Chlebowski T, et al. (2003). Influence of estrogen plus progestin on breast cancer and mammography in healthy postmenopausal women: The Women's Health Initiative randomized trial. JAMA, 289(24): 3243–3253.

4. Shumaker SA, et al. (2003). Estrogen plus progestin and the incidence of dementia and mild cognitive impairment in postmenopausal women. The Women's Health Initiative memory study: A randomized controlled trial. JAMA, 289(20): 2651–2662.

5. North American Menopause Society (2004). Position statement: Recommendations for estrogen and progestogen use in peri- and postmenopausal women: October 2004 position statement of the North American Menopause Society. Menopause, 11(6): 589–600. Available online: http://www.menopause.org/edumaterials/2004HTreport.pdf.

6. Solomon CG, Dluhy RG (2003). Rethinking postmenopausal hormone therapy. New England Journal of Medicine, 348(7): 579–580.

7. Million Women Study Collaborators (2003). Breast cancer and hormone-replacement therapy in the Million Women Study. Lancet, 362(9382): 419–427.

8. American Heart Association (2000). Women, Heart Disease, and Stroke Survey Highlights. Available online: http://www.americanheart.org/presenter.jhtml?identifier=10382.

9. Manson JE, et al. (2003). Estrogen plus progestin and the risk of coronary heart disease. New England Journal of Medicine, 349(6): 523–534.

10. Prentice RL, et al. (2006). Combined analysis of Women's Health Initiative observational and clinical trial data on postmenopausal hormone treatment and cardiovascular disease. American Journal of Epidemiology, 163(7): 589–599.

11. Rossouw JE, et al. (2007). Postmenopausal hormone therapy and risk of cardiovascular disease by age and years since menopause. JAMA, 297(13): 1465–1477.

12. North American Menopause Society (2004). Treatment of menopause-associated vasomotor symptoms: Position statement of the North American Menopause Society. Menopause, 11(1): 11–33.

13. Freedman R, et al. (1995). Biochemical and thermoregulatory effects of behavioral treatment for menopausal hot flashes. Menopause: The Journal of the North American Menopause Society, 2(4): 211–218.

14. Irvin JH, et al. (1996). The effects of relaxation response training on menopausal symptoms. Journal of Psychosomatic Obstetrics and Gynecology, 17(4): 202–207.

15. National Heart, Lung, and Blood Institute (2003). Postmenopausal hormone therapy: Questions and answers. Available online: http://www.nhlbi.nih.gov/health/women/q_a.htm.

16. American College of Obstetricians and Gynecologists (2003). Statement of the American College of Obstetricians and Gynecologists on hormone therapy for the prevention and treatment of postmenopausal osteoporosis. ACOG News Release. Available online: http://www.acog.com/from_home/publications/press_releases/nr10-07-03.cfm.

17. U.S. Food and Drug Administration (2004). FDA plans to evaluate results of Women's Health Initiative study for estrogen-alone therapy. FDA Talk Paper T04-06. Available online: http://www.fda.gov/bbs/topics/ANSWERS/2004/ANS01281.html.

18. Women's Health Initiative Steering Committee (2004). Effects of conjugated equine estrogen in postmenopausal women with hysterectomy. JAMA, 291(14): 1701–1712.

19. Beral V, et al. (2007). Ovarian cancer and hormone replacement therapy in the Million Women Study. Lancet, 369(9574): 1703–1710.

20. Wassertheir-Smoller S (2003). Effect of estrogen plus progestin on stroke in postmenopausal women. The Women's Health Initiative: A randomized trial. JAMA, 289(20): 2673–2684.

21. Grodstein F, et al. (2006). Hormone therapy and coronary heart disease: The role of time since menopause and age at hormone initiation. Journal of Women's Health, 15(1): 35–44.

22. Kerlikowske K, et al. (2003). Prognostic characteristics of breast cancer among postmenopausal hormone users in a screened population. Journal of Clinical Oncology, 21(23): 4314–4321.

23. Prestwood KM, et al. (2003). Ultralow-dose micronized 17 B-estradiol and bone density and bone metabolism in older women. JAMA, 290(8): 1042–1048.

24. Holmberg L, Anderson H (2004). HABITS (Hormonal replacement therapy after breast cancer-Is it safe?), a randomized comparison: Trial stopped. Lancet, 363(9407): 453–455.

Author	Kathe Gallagher, MSW
Editor	Kathleen M. Ariss, MS
Associate Editor	Pat Truman
Associate Editor	Terrina Vail
Primary Medical Reviewer	Joy Melnikow, MD, MPH - Family Medicine
Specialist Medical Reviewer	Carla J. Herman, MD, MPH - Internal Medicine
Last Updated	May 26, 2006