Transgender people have a gender identity that is different from the gender associated with their assigned sex at birth. A transgender man may have been raised as a girl but later identifies as a man. A transgender woman may have been raised as a boy and now identifies as a woman. There are many different gender identities and other ways that people identify besides as a boy/man or a woman/girl. A few terms that represent some of these identities include agender, genderqueer, nonbinary and two-spirit.

Gender dysphoria

Transgender people may experience gender dysphoria, which is a discomfort or distress about ways their body looks that does not match their identity. Some of these may be body shape, having or not having breasts, having facial hair or other physical characteristics that are stereotypically “feminine” when someone has a masculine identity or stereotypically “masculine” when someone has a feminine identity.

Not everyone experiences dysphoria in the same way or about the same things. The opposite of dysphoria is gender euphoria, where someone experiences joy and happiness about how their body matches their identity and the ways other people treat them.

Transitioning

Some transgender people go through a process called transitioning. This includes changing parts of their life so it aligns with their gender identity. There are a few different ways that people can transition. Medical transition is one option that can include a combination of different surgeries and gender-affirming hormone therapy. Access to gender-affirming treatments leads to better mental health in transgender people. Gender-affirming hormone therapy for a transgender man includes taking testosterone. Some of the physiological changes that may occur are a lower voice pitch, more facial and body hair, increased muscle growth, clitoris growth and no longer having a period.

A transgender woman’s gender-affirming hormone therapy includes taking estrogen and medication that reduces testosterone. After starting these medicines, some of the changes include breast growth, decrease in muscle mass, less body and facial hair, fewer erections and slowed scalp hair loss.

Effects of hormone therapy

Before starting hormone therapy, doctors do bloodwork to look at potential risks. Side effects from gender-affirming hormone therapy can include increased risk of blood clots in transgender women and too many red blood cells in transgender men.

There are not many studies on the effects of gender-affirming hormone therapy on different diseases. But, in cisgender people (men and women who are not transgender), there are known sex differences in conditions such as hypertension, kidney disease and autoimmune diseases. Adding gender-affirming hormone therapy may change a person’s risk for developing certain medical conditions.

Learning more about sex differences in health and disease and including more transgender people in research studies can help scientists identify and prevent possible physiological risks of medically transitioning. That, in turn, can lead to even better health care.