FLUCTUATIONS IN WEIGHT, HEMATOCRIT AND PLASMA PROTEIN WITH THE MENSTRUAL CYCLE

Abstract

Blood specimens were collected from 6 normal resident nurses at 3 day intervals throughout a single menstrual cycle. The specimens were analyzed for sodium, potassium, total base, and plasma protein. Hematocrit and body weight readings were also made. When plotted in the absolute values which were obtained, none of the results showed any significance or pattern whatsoever, either individually or collectively. An attempt was then made to demonstrate by statistical methods any patterns which might be present but concealed by individual trends. The individual groups of data were analyzed for trend by fitting a straight line to the chronologic data by the method of least squares. In cases where no trend was observed, fluctuations were computed as deviations from the mean. Where significant trend occurred, variations were computed as deviations from the trend line. All deviations were finally expressed in units of the standard deviation of their own series of data, and so recorded upon graphs. Composite curves were fitted by inspection. By this means, consistent patterns in weight, hematocrit, and plasma protein were found. The weight curve is found to lie well above the base line at about the time of menstruation, and to be reflected by a simultaneous decline in hematocrit and protein. No consistency in Na, K or total base could be demonstrated.