Effects of Progesterone on the Female Genital Tract after Castration Atrophy. ∗

The effects of oestrin-free progestin on the atrophic endometria of 2 castrated monkeys were described by one of us. 1 These animals had been castrated for 37 days and were given 4 RbU of oestrin-free corpus luteum extract daily for 10 days. The endometria of both monkeys showed unquestionable premenstrual development. Although these preparations did not produce eornifkation of the vaginas of castrated rats it could not be stated with certainty that they were entirely free of oestrin and that the observed effects were due only to the action of progestin. We wish here to present results of similar experiments using synthetic progesterone.†

A young adult monkey that had been castrated for 242 days was given 4 mg. of progesterone daily for 18 days, a vaginal biopsy was taken on the eighth day, a thread was placed through the uterus on the eleventh day and the animal was killed on the nineteenth. Nucleated epithelial cells appeared in the vaginal smear and were present in considerable numbers by the eighth day, after which they gradually decreased and were almost absent at the conclusion of the experiment. The face showed coloration by the seventh day and the pale sexual skin developed and maintained a deep red color. The uterus, at laparotomy on the eleventh day, measured 11 by 9 mm. at its greatest diameters and at autopsy 17 by 13.5 mm.

This treatment produced a fully developed premenstrual endometrium and epithelial proliferations 1 characteristic of an implantation site. The cervical glands showed active secretion though the epithelial cells in most places were not as tall as those seen following injections of oestrin. The vaginal mucosa, though thin, showed some stimulation both at the time of biopsy on the eighth day and at autopsy.