Sexual differentiation in humans any androgen can cause external masculinization. The most potent is dihydrotestosterone (DHT), generated from testosterone in skin and genital tissue by the action of 5α-reductase. A male fetus may be incompletely masculinized if this enzyme is deficient. In some diseases and circumstances, other androgens may be present in high enough concentrations to cause partial or (rarely) complete masculinization of the external genitalia of a genetically female fetus. The testes begin to secrete three hormones that influence the male internal and external genitalia. They secrete anti-müllerian hormone, testosterone, and Dihydrotestosterone. anti-Müllerian hormone (AMH) causes the paramesonephric ducts to regress. Testosterone, which
Sexual Preference (book) Sexual Preference (book) Sexual Preference: Its Development in Men and Women (1981) is a book about the development of sexual orientation by the psychologist Alan P. Bell and the sociologists Martin S. Weinberg and Sue Kiefer Hammersmith, in which the authors reevaluate what were at the time of its publication widely held ideas about the origins of heterosexuality and homosexuality, sometimes rejecting entirely the factors proposed as causes, and in other cases concluding that their importance had been exaggerated. Produced with the help of the American National Institute of Mental Health, the study was a publication of the Institute for