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
Sexual frustration For males it could be that they have testicles and no penis; a male might be born without a penis (aphallia) or be born with one and have it removed (penis removal or penectomy). Men can still ejaculate via prostate stimulation in that case. For females they might not have a clitoris which causes sexual pleasure; a female might have had her clitoris forcibly severed (female genital mutilation) or voluntarily removed (female circumcusion) as part of a medical procedure. Involuntary celibacy is a form of sexual frustration. Sexual frustration Sexual frustration in humans is frustration caused by a discrepancy between