Thomas1has reported two cases in which edema occurred regularly and only during menstruation. One of these patients was given hypodermic injections of anterior pituitary extract and later the gonadotropic substance of pregnancy urine. With the latter therapy he was able to prevent the edema. Sweeney2reported observations on the body weight of forty-two normal healthy young women. Thirty per cent showed a gain of 3 or more pounds sometime during the menstrualcycle, usually just before the menstrual flow was established. Some had a true pitting edema. Okey and Stewart3have also followed the weight of twenty women students and found an increase in weight of from 1 to 3 pounds (453 to 1,360 Gm.) in one fourth of their subjects. Almost all the students who showed the gain in weight gave histories of menstrual headaches or discomfort. Eufinger and Spiegler4observed a tendency to