Menstruation and the Anterior Pituitary.

Abstract

The prevailing gynecological opinion in the textbooks and the gynecological literature generally holds that menstruation is due to the degeneration of the corpus luteum and that the menstrual flow proceeds exclusively from a “pregravid” (swollen, congested, secreting) endometrium. We contend that this is a post hoc, propter hoc argument, a time relation mistaken for cause and effect, a conclusion without the slightest experimental evidence.

The chief facts that have called this generally accepted notion in question were the outcome of the work of Geo. W. Corner, who found that periodic uterine bleeding in monkeys often does occur from uteri not at all enlarged and unaccompanied by corpora lutea in the ovaries. This conclusion has been corroborated by a very extensive series of observations involving scores of laparotomies and hundreds of rectal palpations of the organs in fully adult monkeys of the Carnegie colony at Baltimore.

On the basis of these findings and other considerations which will not be taken up at this place, the senior writer has contended 1 that there is an active substance originating outside the ovaries that causes the periodic bleeding which we call menstruation. Over a dozen hypophysectomies (Dr. Firor∗) have enabled us to announce that it is the anterior pituitary that elaborates the substance causing uterine bleeding. The evidence is as follows:

1. Ablation of the hypophysis abolishes the cycle, the sex organs atrophy, the sex skin becomes pale as in the pre-adolescent female.

2. Administration of ovarian hormone (Allen-Doisy in the form of Amniotin Squibb†) to a female monkey, whether ovariectomized or not, causes the bleeding. Even a one-year-old baby, of the “equivalent age” of a 3- or 4-year-old girl, can be made to bleed with as little as 90 rat units.