Prenatal hormones and sexual orientation Only 23% of childhood gender problems will result in transsexuality in adulthood. Drawing on some transsexualism cases, Garcia-Falgueras and Swaab state that "[f]rom these examples it appears that the direct action of testosterone on the developing brain in boys and the lack of such action on the developing brain in girls are crucial factors in the development of male and female gender identity and sexual orientation ... ." Countless studies have been run on peripheral levels of sex steroids in male and female homosexuals, a considerable number of which claimed to find "less 'male hormone' and/or more 'female hormone' in
Transgender hormone therapy (female-to-male) Transgender hormone therapy (female-to-male) Transgender hormone therapy of the female-to-male (FTM) type, also known as masculinizing hormone therapy, is a form of hormone therapy and sex reassignment therapy which is used to change the secondary sexual characteristics of transgender people from feminine (or androgynous) to masculine. It is one of two types of transgender hormone therapy (the other being male-to-female), and is predominantly used to treat transgender men and other transmasculine individuals. Some intersex people also receive this form of therapy, either starting in childhood to confirm the assigned sex or later if the assignment proves to be incorrect. The