Sex hormones and female homosexuality: a critical examination.

To ascertain the validity of hormonal theories of human homosexuality, which are based on animal research, this article reviews psychoendocrine data on lesbian and transsexual women. Sex hormone levels were found to be normal in the majority of homosexual women, but about a third of the subjects studied had elevated androgen levels. In women with prenatal androgen excess, heterosexuality appears to be more frequent than bisexuality, and exclusive homosexuality is rare. Two recent reports suggest abnormalities of the neuroendocrine regulation of LH secretion in female transsexuals. Clearly, prenatal or postpubertal hormone levels do not determine the development of sexual orientation, but a facilitating neuroendocrine predisposition cannot be ruled out at present.