Changes in anthropometry with testosterone therapy in a female with gender identity disorder

A 31-year-old regularly menstruating Japanese female was referred to our outpatient clinic by a psychiatrist. She had been diagnosed as having gender identity disorder by detailed counseling and clinical intervention 3 years earlier. After obtaining fully informed written consent, we treated her with 125 mg of testosterone enanthate, intramuscularly, every 2 weeks for 4 months. Serum testosterone levels increased to the normal male value (from 28 to 432 ng/dL). Although menstrual cycle remained regular, her voice became lower after 4 months of therapy. Body weight, body mass index, and lean body mass increased, while body fat mass and percentage of body fat decreased. However, trunk-leg fat ratio did not change during the observation period. During testosterone therapy, a disproportionate increase in lean body mass and decrease in body fat mass are early onset events, while the shift toward upper body fat distribution may be a late onset event along with increase in BMD.