Some transgender women use estrogen as part of their hormone therapy for gender affirmation. Estrogen helps transgender women align their bodies with their female gender identity. Gender affirmation with hormone therapy has benefits such as improved quality of life and reduced depression, anxiety, and suicidal thoughts. However, estrogen use in transgender women may have long-term risks to heart health.

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A recent PCORI-funded study found that transgender women taking estrogen for gender affirmation had a higher risk of stroke and blood clots than nontransgender women and nontransgender men. The highest risk differences were found several years after starting estrogen.


Working with Your Doctor to Avoid Health Problems from Using Estrogen

Learn about the benefits and risks of using estrogen, as well as about any other gender-affirming hormone therapy options.
Schedule regular check-ups with your primary care doctor to check your heart health while using estrogen, even if you’ve stopped using estrogen.
Information about healthcare practices for transgender patients taking hormones is available to you and your primary care doctor through the World Professional Association for Transgender Health (WPATH) and the Center of Excellence for Transgender Health at the University of California San Francisco.

What You Can Do to Reduce Your Risk for Blood Clots and Stroke

Organizations such as the American Heart Association provide advice on ways to reduce your risk of getting a blood clot or having a stroke. This advice includes the following:

If you smoke, work on stopping. Smoking further increases your risk for clots and stroke. Ask your doctor about getting help to quit smoking.
Stay physically active. Finding activities you like to do, such as dancing or walking with friends, can help.
Make healthy food choices.
Have your blood pressure checked regularly.
Talk to your doctor about how to recognize the signs of blood clots and strokes. Symptoms of blood clots include swelling, pain or tenderness, discoloration and unusual warmth in an arm or leg, chest pain and heavy breathing, shortness of breath, sudden cough, and chronic headaches. Symptoms of stroke can be remembered using the letters F-A-S-T:

Face Drooping
Arms Weakened
Speech Slurred
Time to Call 9-1-1

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About the Evidence

These results are part of a larger study looking at health outcomes for transgender people. The research team compared health outcomes in transgender women with outcomes in nontransgender women and nontransgender men. The team reviewed the medical records of transgender and nontransgender people for up to 10 years.

Read more about this study at:

Logos for PCORI, the National LGBT Health Education Center (a program of the Fenway Institute), and WPATH: World Professional Association for Transgender Health

Download this Evidence Update


1. Getahun D, Nash R, Flanders WD, et al. Cross-sex Hormones and Acute Cardiovascular Events in Transgender Persons: A Cohort Study. Ann Intern Med. 2018;169(4):205-213.
2. Owen-Smith AA, Gerth J, Sineath RC, et al. Association Between Gender Confirmation Treatments and Perceived Gender Congruence, Body Image Satisfaction, and Mental Health in a Cohort of Transgender Individuals. The Journal of Sexual Medicine. 2018;15(4):591-600.
3. Rowniak S, Bolt L, Sharifi C. The Effect of Cross-sex Hormones on the Quality of Life, Depression and Anxiety of Transgender Individuals: A Quantitative Systematic Review. JBI Database of Systematic Reviews and Implementation Reports. 2019;17(9):1826-1854.
4. Coleman E, Bockting W, Botzer M, et al. Standards of Care for the Health of Transsexual, Transgender, and Gender-Nonconforming People. 7th ed. Minneapolis, MN: World Professional Association for Transgender Health; 2012. Accessed January 16, 2020.
5. Deutsch MB, ed. Guidelines for the Primary and Gender-Affirming Care of Transgender and Gender Nonbinary People. 2nd ed. San Francisco: UCSF Transgender Care, Department of Family and Community Medicine, University of California San Francisco; 2016. Accessed January 16, 2020.
6. American Heart Association. Healthy Living. Accessed January 16, 2020.
7. National Blood Clot Alliance. Stop The Clot. Accessed January 16, 2020.
8. American Stroke Association. Stroke Symptoms. Accessed January 16, 2020.

The information in this publication is not intended to be a substitute for professional medical advice. This update summarizes findings from a PCORI research award to Emory University.

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