Failure of ovulation after neonatal administration of 5 alpha-dihydrotestosterone to female rats.

Wistar female rats were injected with testosterone (T) or 5 alpha-dihydrotestosterone (5 alpha-DHT) from the day of birth (= day 1) to day 5. Neonatal treatment with 1 mg of T resulted in anovulatory persistent estrous syndrome in 100% of the animals. In the females treated with 1 mg of 5 alpha-DHT, 88.2% of the treated rats were sterile at 120 days of age. Treatment with 0.5 mg 5 alpha-DHT was also effective in inducing anovulatory sterility, the incidence of sterility being 71.4%. In the females injected with 0.1 mg 5 alpha-DHT, 42.9% of the animals were anovulatory at 120 days of age. These results suggest that non-aromatizable androgen, 5 alpha-DHT, can permanently suppress the development of female type of neuroendocrine regulation.