THE ANTERIOR LOBE AND MENSTRUATION

Abstract

Injections of Allen-Doisy hormone (e.g., in the form of Amniotin Squibb) have been known to cause bleeding in ? monkeys, whether normal or castrated. It is here shown that this also occurs consistently in baby monkeys 1300 to 1700 gm. in weight, about a year old and 21/2 to 3 yrs. before the menarche[long dash]that is, corresponding to a human child 3 or 4 yrs. of age. That this effect is not a direct one is shown by the fact that hypophy-sectomy abolishes it. But bleeding occurs in hypophysectomized as well as normal animals upon injection of anterior lobe extracts or by implants of the fresh gland. This is interpreted as a direct effect. A physiological basis of uterine bleeding is, therefore, for the 1st time demonstrated. It seems reasonable to postulate a separate anterior lobe hormone as the direct cause of bleeding, since it is here demonstrated that the bleeding is independent of the follicle stimulating effect of Smith and Engle and the luteinizing phenomenon of Evans and Simpson and other influences attributed to the gland. With the treatments here outlined bleeding may result from a uterus that shows not the slightest macroscopic change. Hence the threshold for bleeding is far below that causing "oestrous" changes (growth, edema, congestion) in uterus or ovaries. This has adaptive significance, for the prime and original function of the bleeding is that of supplying blood cells (perhaps for Fe) directly to the embryo in early pregnancy; "oestrous" changes would be disastrous to the continuance of pregnancy. Since uterine bleeding may be caused so much more readily than hyperplasia of dormant reproductive tract and ovaries, the gynecologist must determine what benefit the patient receives from a mere bleeding without the usual concomitant "oestrous," not to mention pregravid changes.