Feminizing hormone therapy

Date Updated: 11/01/2022

Overview

Feminizing hormone therapy typically is used by transgender women and nonbinary people to produce physical changes in the body that are caused by female hormones during puberty. Those changes are called secondary sex characteristics. This hormone therapy helps better align the body with a person's gender identity. Feminizing hormone therapy also is called gender-affirming hormone therapy.

Feminizing hormone therapy involves taking medicine to block the action of the hormone testosterone. It also includes taking the hormone estrogen. Estrogen lowers the amount of testosterone the body makes. It also triggers the development of feminine secondary sex characteristics. Feminizing hormone therapy can be done alone or along with feminizing surgery.

Not everybody chooses to have feminizing hormone therapy. It can affect fertility and sexual function, and it might lead to health problems. Talk with your health care provider about the risks and benefits for you.

Why it's done

Feminizing hormone therapy is used to change the body's hormone levels. Those hormone changes trigger physical changes that help better align the body with a person's gender identity.

In some cases, people seeking feminizing hormone therapy experience discomfort or distress because their gender identity differs from their sex assigned at birth or from their sex-related physical characteristics. This condition is called gender dysphoria.

Feminizing hormone therapy can:

Improve psychological and social well-being.
Ease psychological and emotional distress related to gender.
Improve satisfaction with sex.
Improve quality of life.

Your health care provider might advise against feminizing hormone therapy if you:

Have a hormone-sensitive cancer, such as prostate cancer.
Have problems with blood clots, such as when a blood clot forms in a deep vein, a condition called deep vein thrombosis, or a there's a blockage in one of the pulmonary arteries of the lungs, called a pulmonary embolism.
Have significant medical conditions that haven't been addressed.
Have behavioral health conditions that haven't been addressed.
Have a condition that limits your ability to give your informed consent.

Risks

Research has found that feminizing hormone therapy can be safe and effective when delivered by a health care provider with expertise in transgender care. Talk to your health care provider about questions or concerns you have regarding the changes that will happen in your body as a result of feminizing hormone therapy.

Complications can include:

Blood clots in a deep vein or in the lungs
Heart problems
High levels of triglycerides, a type of fat, in the blood
High levels of potassium in the blood
High levels of the hormone prolactin in the blood
Nipple discharge
Weight gain
Infertility
High blood pressure
Type 2 diabetes
Stroke

Evidence suggests that people who take feminizing hormone therapy may have an increased risk of breast cancer when compared to cisgender men — men whose gender identity aligns with societal norms related to their sex assigned at birth. But the risk is not greater than that of cisgender women.

To minimize risk, the goal for people taking feminizing hormone therapy is to keep hormone levels in the range that's typical for cisgender women.

Fertility

Feminizing hormone therapy might limit your fertility. If possible, it's best to make decisions about fertility before starting treatment. The risk of permanent infertility increases with long-term use of hormones. That is particularly true for those who start hormone therapy before puberty begins. Even after stopping hormone therapy, your testicles might not recover enough to ensure conception without infertility treatment.

If you want to have biological children, talk to your health care provider about freezing your sperm before you start feminizing hormone therapy. That procedure is called sperm cryopreservation.

How you prepare

Before you start feminizing hormone therapy, your health care provider assesses your health. This helps address any medical conditions that might affect your treatment. The evaluation may include:

A review of your personal and family medical history.
A physical exam.
Lab tests.
A review of your vaccinations.
Screening tests for some conditions and diseases.
Identification and management, if needed, of tobacco use, drug use, alcohol use disorder, HIV or other sexually transmitted infections.
Discussion about sperm freezing and fertility.

You also might have a behavioral health evaluation by a provider with expertise in transgender health. The evaluation may assess:

Gender identity.
Gender dysphoria.
Mental health concerns.
Sexual health concerns.
The impact of gender identity at work, at school, at home and in social settings.
Risky behaviors, such as substance use or use of unapproved silicone injections, hormone therapy or supplements.
Support from family, friends and caregivers.
Your goals and expectations of treatment.
Care planning and follow-up care.

People younger than age 18, along with a parent or guardian, should see a medical care provider and a behavioral health provider with expertise in pediatric transgender health to discuss the risks and benefits of hormone therapy and gender transitioning in that age group.

What you can expect

You should start feminizing hormone therapy only after you've had a discussion of the risks and benefits as well as treatment alternatives with a health care provider who has expertise in transgender care. Make sure you understand what will happen and get answers to any questions you may have before you begin hormone therapy.

Feminizing hormone therapy typically begins by taking the medicine spironolactone (Aldactone). It blocks male sex hormone receptors — also called androgen receptors. This lowers the amount of testosterone the body makes.

About 4 to 8 weeks after you start taking spironolactone, you begin taking estrogen. This also lowers the amount of testosterone the body makes. And it triggers physical changes in the body that are caused by female hormones during puberty.

Estrogen can be taken several ways. They include a pill and a shot. There also are several forms of estrogen that are applied to the skin, including a cream, gel, spray and patch.

It is best not to take estrogen as a pill if you have a personal or family history of blood clots in a deep vein or in the lungs, a condition called venous thrombosis.

Another choice for feminizing hormone therapy is to take gonadotropin-releasing hormone (Gn-RH) analogs. They lower the amount of testosterone your body makes and might allow you to take lower doses of estrogen without the use of spironolactone. The disadvantage is that Gn-RH analogs usually are more expensive.

After you begin feminizing hormone therapy, you'll notice the following changes in your body over time:

Fewer erections and a decrease in ejaculation. This will begin 1 to 3 months after treatment starts. The full effect will happen within 3 to 6 months.
Less interest in sex. This also is called decreased libido. It will begin 1 to 3 months after you start treatment. You'll see the full effect within 1 to 2 years.
Slower scalp hair loss. This will begin 1 to 3 months after treatment begins. The full effect will happen within 1 to 2 years.
Breast development. This begins 3 to 6 months after treatment starts. The full effect happens within 2 to 3 years.
Softer, less oily skin. This will begin 3 to 6 months after treatment starts. That's also when the full effect will happen.
Smaller testicles. This also is called testicular atrophy. It begins 3 to 6 months after the start of treatment. You'll see the full effect within 2 to 3 years.
Less muscle mass. This will begin 3 to 6 months after treatment starts. You'll see the full effect within 1 to 2 years.
More body fat. This will begin 3 to 6 months after treatment starts. The full effect will happen within 2 to 5 years.
Less facial and body hair growth. This will begin 6 to 12 months after treatment starts. The full effect happens within three years.

Some of the physical changes caused by feminizing hormone therapy can be reversed if you stop taking it. Others, such as breast development, cannot be reversed.

Results

While on feminizing hormone therapy, you meet regularly with your health care provider to:

Keep track of your physical changes.
Monitor your hormone levels. Over time, your hormone dose may need to change to ensure you are taking the lowest dose necessary to get the physical effects that you want.
Have blood tests to check for changes in your cholesterol, blood sugar, blood count, liver enzymes and electrolytes that could be caused by hormone therapy.
Monitor your behavioral health.

You also need routine preventive care. Depending on your situation, this may include:

Breast cancer screening. This should be done according to breast cancer screening recommendations for cisgender women your age.
Prostate cancer screening. This should be done according to prostate cancer screening recommendations for cisgender men your age.
Monitoring bone health. You should have bone density assessment according to the recommendations for cisgender women your age. You may need to take calcium and vitamin D supplements for bone health.