Feminizing hormone therapy is used to induce physical changes in your body caused by female hormones during puberty (secondary sex characteristics) to promote the matching of your gender identity and your body (gender congruence). If feminizing hormone therapy is started before the changes of male puberty begin, male secondary sex characteristics, such as increased body hair and changes in voice pitch, can be avoided. Feminizing hormone therapy is also referred to as cross-sex hormone therapy.
During feminizing hormone therapy, you'll be given medication to block the action of the hormone testosterone. You'll also be given the hormone estrogen to decrease testosterone production and induce feminine secondary sex characteristics. Changes caused by these medications can be temporary or permanent. Feminizing hormone therapy can be done alone or in combination with feminizing surgery.
Feminizing hormone therapy isn't for all transgender women, however. Feminizing hormone therapy can affect your fertility and sexual function and cause other health problems. Your doctor can help you weigh the risks and benefits.
Feminizing hormone therapy is used to alter your hormone levels to match your gender identity. Typically, people who seek feminizing hormone therapy experience distress due to a difference between experienced or expressed gender and sex assigned at birth (gender dysphoria). To avoid excess risk, the goal is to maintain hormone levels in the normal range for the target gender.
Feminizing hormone therapy can:
Although use of hormones is currently not approved by the Food and Drug Administration for the treatment of gender dysphoria, research suggests that it can be safe and effective.
If used in an adolescent, hormone therapy typically begins at age 16. Ideally, treatment starts before the development of secondary sex characteristics so that teens can go through puberty as their identified gender. Hormone therapy is not typically used in children.
Feminizing hormone therapy isn't for all trans women. Your doctor might discourage feminizing hormone therapy if you:
Talk to your doctor about the changes in your body and any concerns you might have. Complications of feminizing hormone therapy might include:
Current evidence indicates that there is no increased risk of breast cancer.
Because feminizing hormone therapy might reduce your fertility, you'll need to make decisions about future childbearing before starting treatment. The risk of permanent infertility increases with long-term use of hormones, especially when hormone therapy is initiated before puberty. Even after discontinuation of hormone therapy, testicular function might not recover sufficiently to ensure conception.
If you want to have biological children, talk to your doctor about freezing your sperm (sperm cryopreservation) before beginning feminizing hormone therapy.
Other side effects of estrogen use in trans women include reduced libido, erectile function and ejaculation. Erectile function might improve with the use of oral medications such as sildenafil (Viagra) or tadalafil (Adcirca, Cialis).
Before starting feminizing hormone therapy, your doctor will evaluate your health to rule out or address any medical conditions that might affect or contraindicate treatment. The evaluation might include:
You might also need a mental health evaluation by a provider with expertise in transgender health. The evaluation might assess:
Adolescents younger than age 18, accompanied by their parents or guardians, also should see doctors and mental health providers with expertise in pediatric transgender health to discuss the risks of hormone therapy, as well as the effects and possible complications of gender transition.
Typically, you'll begin feminizing hormone therapy by taking the diuretic spironolactone (Aldactone) at doses of 100 to 200 milligrams daily. This blocks male sex hormone (androgen) receptors and can suppress testosterone production.
After six to eight weeks, you'll begin taking estrogen to decrease testosterone production and induce feminization. Estrogen can be taken in a variety of methods, including as a pill, by injection or in skin preparations, such as a cream, gel, spray or patch. Don't take estrogen orally, however, if you have a personal or family history of venous thrombosis. Use of gonadotropin-releasing hormone (Gn-RH) analogs to suppress testosterone production might allow you to take lower estrogen doses and wouldn't require the use of spironolactone. However, Gn-RH analogs are more expensive.
Additional therapies might include:
Feminizing hormone therapy will begin producing changes in your body within weeks to months. Your timeline might look as follows:
During your first year of feminizing hormone therapy, you'll need to see your doctor approximately every three months for checkups, as well as anytime you make changes to your hormone regimen. Your doctor will:
After feminizing hormone therapy, you will also need routine preventive care, including: