Hypospadias and Non-descent of the Testes caused in Rats by Progesterone

Abstract

Hain¹, Wiesner², Greene and Ivy³ have reported the occurrence of hypospadias in young female rats following the injection of œstrogens or androgens (œstrone, androstanediol, testosterone) into the pregnant mothers or into the young soon after birth. Lacassagne⁴ has observed a similar lesion in a male rabbit treated from birth with œstrone. I also have observed hypospadias in female rats and mice treated from birth with œstrone or testosterone. The males have not shown any malformation of the penis; but their testes have failed to descend into the scrotum at the normal time. In a recent experiment, fifteen new-born Wistar rats were given subcutaneous injections of 0.5 mgm. progesterone in sesame oil on each of the three post-natal days, and 1 mgm. was given three times a week until the twenty-third day, after which no further treatment was applied except that on the forty-fourth day 2 mgm. progesterone were given to each of the males. At this time the eight females all showed hypospadias and the seven males all had undescended testes. On the sixty-fifth day two only of the males have testes in the scrotum. Normally the testes would have descended not later than the fortieth day.