5 alpha-reduced androgens in the human fetal testis.

The androgen content was measured in testes from 34 male and in ovaries from 30 female embryos that varied in age from less than 12 to approximately 20 weeks. The 5 alpha-reduced androgens dihydrotestosterone and 3 alpha-androstanediol were found in testes at a level of about a 30th of that of testosterone at all ages examined, whereas very little or no testosterone, androstenedione, or either of the 5 alpha-reduced androgens were detected in the ovaries. Whether dihydrotestosterone plays a role in the development of the testes is unknown.