The pros and cons of taking estrogen pills for menopause and gender transition

• Estrogen pills can help relieve menopausal symptoms like hot flashes and vaginal dryness.
• Discuss with a doctor about taking progestin with estrogen to reduce endometrial cancer risk.
• Estrogen pills can help facilitate gender transition by enhancing feminine features like rounder hips.
• Visit Insider's Health Reference library for more advice.

Estrogen pills contain the hormone estrogen and are mainly used to treat symptoms of menopause or for gender affirmation of transgender women. 

Estrogen pills are very effective at controlling the symptoms of menopause and facilitating transition, says Maggie Pham, DO, an OB-GYN at Pomona Valley Hospital Medical Center. 

As a side effect, they can also reduce the risk of osteoporosis and, in some cases, colon cancer. They may also increase risk for breast and endometrial cancer, blood clots, and heart disease, however the research around these risks is still ongoing and may vary based on factors like age. 

"The pros and cons of estrogen use should be considered against the individual's age, personal medical history, severity of symptoms, and goals of treatment," Pham says. 

Here we explain the benefits and drawbacks of estrogen pills so you can discuss with your doctor whether they're right for you. 

Menopause

As a person enters menopause, their estrogen levels drop significantly. This leads to many of the symptoms of menopause, including hot flashes and vaginal dryness. 

Estrogen pills are one of the most effective treatments available for these symptoms helping "women transition more gracefully into menopause," says Pham. Estrogen comes in other forms like patches and injections that can work equally well.

We note here that a large 2002 study found that taking estrogen may come with an increased risk for cancer and stroke. However, subsequent studies have called those findings into question stating that the 2002 study was "inadequately designed, evaluated, and reported."

In fact, numerous studies have since found that those who are premenopausal or early postmenopausal actually saw a reduced risk in coronary disease from hormone replacement therapy. 

Moreover, the American College of Obstetricians and Gynecologists states that hormone therapy may also reduce the risk of colon cancer and osteoporosis. When estrogen is taken with progestin for people with a uterus, it may also slightly reduce the risk of endometrial cancer. But it may slightly increase the risk for breast cancer. 

With that in mind it's important to discuss your medical history with your doctor to assess whether taking estrogen is best and safest for you.

If you're considering estrogen pills for menopause just make sure you follow some of the following safety guidelines:

• Have an open conversation with your doctor about the risks and benefits.
• While taking estrogen pills, check in annually to reevaluate.
• People with a uterus must take estrogen pills alongside the hormone progestin (aka hormone replacement therapy) to reduce the risk of uterine cancer.
• Hormone replacement therapy is safest when it's done for less than five years, in the lowest effective dose, and only given before the age of 60. 
• Women without a uterus can take estrogen pills alone, aka estrogen therapy.

Transgender

"Estrogen is a feminizing hormone and helps male-to-female transgender individuals achieve a more feminine appearance including fuller breasts, softer skin, and rounder hips," says Donna Gin Baick, MD, an OB-GYN at University of California Irvine Health. 

This process is known as feminizing hormone therapy and typically involves taking estrogen along with testosterone blockers (which block the production of male hormones) and progesterones.

The physical, emotional, mental, and sexual effects of taking estrogen are evident within about six months, Pham says. The maximum effect of estrogen can be seen within one to five years.

During the first five years, the effects of estrogen can be reversed to a certain degree, and the feminizing effects will wane if someone stops taking estrogen. If you're taking estrogen to transition you should speak with your doctor about your goals and health considerations. 

Althoughion to the clotting and cardiovascular side effects that estrogen has for cisgender females, transgender females will also experience sexual side effects of estrogen, which include:

• Decreased number of erections and less ability for penetrative sex
• Reduction of testicle size
• Decreased sperm count, which may affect fertility 

The cancer risk from estrogen is different for trans women compared to cisgender women. Trans females who take estrogen have a higher breast cancer risk than cis males, but a lower risk than cis females. 

Who shouldn't take estrogen pills

In most cases, deciding to take estrogen comes down to a cost-benefit analysis that you and your doctor do. 

"The decision to start estrogen therapy should be individualized to each person," says Pham. 

However, in most cases you should not take estrogen pills if you are pregnant or may become pregnant, or if you have had:

• Breast or endometrial cancer
• Stroke or heart attack 
• Blood clots
• Liver disease

Since smoking also increases the risk for cardiovascular disease and blood clots, most doctors urge smokers to quit before taking estrogen pills. 

Other symptoms of hormone therapy, besides increased risk for cancer, clots, and cardiovascular disease, include:

• Vaginal bleeding
• Breast soreness
• Bloating
• Headaches

Other types of estrogen therapy

In addition to pills, estrogen is available in transdermal patches, topical gels and creams, and vaginal rings. These can be used to treat menopause symptoms, and other conditions including pain during sex or chronic urinary tract infections in older females, says Pham. 

Insider's takeaway

Whether or not to take estrogen pills is a complex medical decision that should be made after frank, open conversation with your doctor. 

Estrogen pills are the most effective way of treating menopause symptoms, and one of the best non-surgical options for gender affirmation. However, the pills come with certain risks. 

"Patients who are interested in starting estrogen pills or any hormone therapy should discuss with their health care provider to determine if this is right for her," says Gin Baick.