Oestrogen and anti-androgen therapy for transgender women.

Transgender women experience lifelong gender dysphoria due to a gender assignment at birth that is incongruent with their gender identity. They often seek hormone therapy, with or without surgery, to improve their gender dysphoria and to better align their physical and psychological features with a more feminine gender role. Some of the desired physical changes from oestrogen and anti-androgen therapy include decreased body and facial hair, decreased muscle mass, breast growth, and redistribution of fat. Overall the risks of treatment are low, but include thromboembolism, the risk of which depends on the dose and route of oestrogen administration. Other associated conditions commonly seen in transgender women include increased risks of depression and osteoporosis. The risk of hormone-sensitive cancer seems to be low in transgender women, with no increased risk of breast cancer compared with women and no increase in prostate cancer when compared with men. The evidence base for the care of transgender women is limited by the paucity of high-quality research, and long-term longitudinal studies are needed to inform future guidelines.