Masculinizing hormone therapy

Overview

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

Masculinizing hormone therapy involves taking the male hormone testosterone. It stops menstrual cycles and decreases the ovaries' ability to make estrogen. Masculinizing hormone therapy can be done alone or along with masculinizing surgery.

Not everybody chooses to have masculinizing 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

Masculinizing 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 masculinizing 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.

Masculinizing 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 masculinizing hormone therapy if you:

• Are pregnant
• Have a hormone-sensitive cancer, such as breast 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 masculinizing 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 masculinizing hormone therapy.

Complications can include:

• Weight gain
• Acne
• Developing male-pattern baldness
• Sleep apnea
• A rise in cholesterol, which may increase the risk of heart problems
• High blood pressure
• Making too many red blood cells — a condition called polycythemia
• Type 2 diabetes
• Blood clots in a deep vein or in the lungs
• Infertility
• Drying and thinning of the lining of the vagina
• Pelvic pain
• Discomfort in the clitoris

Evidence suggests that people who have masculinizing hormone therapy don't have an increased risk of breast cancer, endometrial cancer or heart disease when compared to cisgender women — women whose gender identity aligns with societal norms related to their sex assigned at birth.

It's unclear whether masculinizing hormone therapy raises the risk of ovarian and uterine cancer. Further research is needed.

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

Fertility

Masculinizing 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 ovaries and uterus might not recover enough for you to become pregnant without infertility treatment.

If you want to have biological children, talk to your health care provider about your choices. They may include:

• Egg freezing. This procedure also is called mature oocyte cryopreservation. Egg freezing has multiple steps that involve triggering ovulation, retrieving the eggs and then freezing them.
• Embryo freezing. This process also is known as embryo cryopreservation. If you want to freeze embryos, you'll need to have the eggs fertilized before they are frozen.
• Ovarian tissue cryopreservation. With this procedure, ovarian tissue is removed, frozen, and later thawed and reimplanted.

Although testosterone might limit your fertility, you still can become pregnant if you have your uterus and ovaries and you have sex with a person who produces sperm. If you want to avoid pregnancy, use birth control consistently. Talk with your health care provider about the form of birth control that's best for your situation.

How you prepare

Before you start masculinizing 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 birth control, fertility and sexual function

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 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 masculinizing 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.

Masculinizing hormone therapy typically begins by taking testosterone. A low dose of testosterone is prescribed, and then the dose is slowly increased over time. Testosterone usually is given through a shot, also called an injection, or through a gel or patch applied to the skin. Other forms of testosterone that may be appropriate for some people include testosterone pellets placed under the skin, a prolonged action injection and an oral capsule taken twice a day.

The testosterone that's used for masculinizing hormone therapy is identical to the hormone that the testicles and ovaries make naturally. Don't use synthetic androgens, such as oral methyl testosterone or anabolic steroids. They can harm your liver and cannot be accurately monitored.

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

• Menstruation stops. This will occur within 2 to 6 months of starting treatment.
• Voice deepens. This will begin 3 to 12 months after you start treatment. You'll see the full effect within 1 to 2 years.
• Facial and body hair grows. This will begin 3 to 6 months after treatment starts. The full effect will happen within 3 to 5 years.
• Body fat is redistributed. This will begin within 3 to 6 months. You'll see the full effect within 2 to 5 years.
• Clitoris become larger, and the vaginal lining thins and become drier. This will begin 3 to 12 months after treatment starts. The full effect will happen in about 1 to 2 years.
• Muscle mass and strength increases. This will begin within 6 to 12 months. You'll see the full effect within 2 to 5 years.

If menstrual bleeding doesn't stop after you've taken testosterone for several months, your health care provider might recommend that you take medicine to stop it.

Some of the physical changes caused by masculinizing hormone therapy can be reversed if you stop taking testosterone. Others, such as a deeper voice, a larger clitoris, scalp hair loss, and increased body and facial hair, cannot be reversed.

Results

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

• Keep track of your physical changes.
• Monitor your hormone levels. Over time, your dose of testosterone may need to change to ensure you are taking the lowest dose necessary to get the physical effects that you want.
• Have lab 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.
• Cervical cancer screening. This should be done according to cervical cancer screening recommendations for cisgender women your age. Be aware that masculinizing hormone therapy can cause your cervical tissues to thin. That can look like a condition called cervical dysplasia in which unusual cells are found on the surface of the cervix. If you have questions or concerns about this, talk to your health care provider.
• Monitoring bone health. You should have bone density assessment according to the recommendations for cisgender men your age. You may need to take calcium and vitamin D supplements for bone health.