Hormone replacement therapy can be either estrogen alone (called estrogen replacement therapy, or ERT), or estrogen and progesterone combined. This combination is referred to as hormone replacement therapy (HRT). Progesterone is usually given in the form of progestins, which are synthetic forms of the naturally occurring hormone progesterone. While once widely used, HRT now has a more limited role because of concerns about its safety.
Estrogen is most commonly given in these forms:
Progestin is available in these forms:
The hormones provided with HRT are meant to replace the natural hormones that a woman's body no longer produces after menopause. Estrogen is involved in many functions in the body, and therefore, HRT is believed to provide the following benefits:
Long-term use of HRT (estrogen plus progestin) may significantly increase women's risks of breast cancer, strokes, heart attacks, and blood clots. ERT may also increase the risk of ovarian cancer. HRT has been associated with an increased risk of gastroesophageal reflux disease (GERD).
For many women the risks of HRT—especially when used long-term—may outweigh the benefits, so the decision to use HRT should be carefully considered and discussed with your doctor.
Women with the following conditions are usually advised not to take HRT:
You and your doctor will determine the dosing schedule that is best for you. You should have an appointment every 3-6 months while taking HRT to discuss the effects and review your decision. The US Food and Drug Administration (FDA) recommends that women who decide to use HRT for menopausal symptoms use the lowest possible dose for the shortest time needed.
There are two general schedules for taking HRT in pill form:
Take estrogen at the same time every day to minimize side effects. If you are using an estrogen skin patch, be sure to read the application directions carefully before using.
The following side effects may disappear over time as your body adjusts to taking HRT. Also, your doctor may be able to change the amount of hormone you receive, the way it is taken, or the timing of the dose, in order to help minimize these effects:
HRT can also cause some very serious side effects. You should discuss your specific health status and risks with your doctor when deciding whether or not to use HRT. These serious side effects include the following:
For a woman who has not had her uterus removed (via a hysterectomy), taking estrogen alone (ERT) can lead to cancer of the endometrium (the lining of the uterus). However, this risk can be avoided by taking both estrogen and progestin in the form of HRT. A woman who has had her uterus removed cannot develop endometrial cancer so she can take ERT.
Some studies have suggested that women who take HRT and ERT are at greater risk for developing breast cancer. A major study on HRT, the Women's Health Initiative, found that invasive breast cancer was more common among women on long-term HRT.
Both HRT and ERT slightly increase the risk of developing blood clots in veins. In the Women's Health Initiative study, women who were long-term users of HRT had twice the number of blood clots as the women who were not taking HRT.
Although HRT was previously believed to reduce the risk of cardiovascular disease, it appears that long-term use of HRT may actually increase this risk. In the Women's Health Initiative study on HRT, women on long-term HRT had increased risk of heart disease and strokes. However, in another study, the risk of heart attacks and death in recently postmenopausal women was the same as women not taking HRT. Debate continues wether or not HRT increases your risk for heart attacks, but it does increase your risk for strokes. Also, it is well established currently that it does not protect you from heart attacks.
To treat the following:
With every medicine, there are important precautions to consider. These include allergies, interactions with other drugs and medical conditions, and safety in certain age groups.
American Congress of Obstetricians and Gynecologists
Healthy Women—National Women's Health Resource Center, Inc.
Canadian Women's Health Network
Women's Health Matters
Furie KL, Kasner SE, Adams RJ, et al. Guidelines for the Prevention of Stroke in Patients With Stroke or Transient Ischemic Attack: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2010 October 21. Available at: http://stroke.ahajournals.org/cgi/reprint/STR.0b013e3181f7d043v1. Updated October 21, 2010. Accessed February 6, 2015.
Hormonal replacement therapy. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated May 2, 2014. Accessed February 6, 2015.
Hormonal replacement therapy doses and preparations. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated November 13, 2012. Accessed February 6, 2015.
Hormones and menopause. National Institute on Aging website. Available at: http://www.nia.nih.gov/HealthInformation/Publications/hormones.htm. Updated January 22, 2015. Accessed February 6, 2015.
Menopause. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated February 5, 2015. Accessed February 6, 2015
Menopause. Women's Health—US Department of Health and Human Services website. Available at: http://womenshealth.gov/menopause/symptom-relief-treatment/menopausal-hormone-therapy.html. Updated September 22, 2010. Accessed February 6, 2015.
Menopause and hormones. US Food and Drug Aministration website. Available at: http://www.fda.gov/ForConsumers/ByAudience/ForWomen/ucm118624.htm. Updated December 2, 2014. Accessed February 6, 2015.
Turner syndrome. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated January 20, 2015. Accessed February 6, 2015.
Schierbeck LL, Rejnmark L, Tofteng CL, Stilgren L, Eiken P, Mosekilde L, Køber L, Jensen JE. Effect of hormone replacement therapy on cardiovascular events in recently postmenopausal women: randomised trial. BMJ. 2012 Oct 9;345.
9/30/2008 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Jacobson BC, Moy B, Colditz GA, Fuchs CS. Postmenopausal hormone use and symptoms of gastroesophageal reflux. Arch Intern Med. 2008;168:1798-1804.
Last reviewed January 2015 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.