PREVENTION OF EXPERIMENTAL UTERINE AND EXTRAUTERINE FIBROIDS BY TESTOSTERONE AND PROGESTERONE1

Abstract

31 castrated [male] guinea pigs were subjected to a prolonged treatment with estradiol; 52 castrated [female][female] were treated simultaneously with estradiol and testosterone, or with estradiol and progesterone. Uterine fibroids were completely prevented by injecting quantities of testosterone (propionate) 50 times greater than that of the injected estradiol (monobenzoate), or by injecting quantities of progesterone 150 times greater than that of the injected estradiol (monobenzoate). Complete prevention of uterine fibroids was also obtained with tablets of progesterone implanted under the skin simultaneously with the tumorigenic tablet of free estradiol. In these expts. with tablets the avg. proportion of absorbed estradiol and progesterone sufficient to prevent fibroids was of 1:13 only. The extrauterine fibrous reaction due to estradiol was pre-vented to a very considerable degree (90 or 95% of prevention).