Androgens-induced atresia of the vagina in Sprague-Dawley female rats.

Atresia or stricture of the orifice of vagina was detected in 100% of female Sprague-Dawley rats injected subcutaneously within 24 hours after birth with testosterone propionate (1mg), 5 alpha-dihydrotestosterone (1mg) or 5 alpha-androstane-3 alpha, 17 beta-diol (1mg) but was not found in any neonatally intact female rats. On the contrary, a single injection of estra-1,3,5(10)-triene-3,17 beta-diol (10 micrograms) in female rats had no effects. When 5 alpha-dihydrotestosterone (1mg) was given into female rats at 0, 1, 2, 3 or 5 days of age, the incidences of the atresia were 85.7%, 63.6%, 25.0%, 0%, and 0%, respectively.