Premenstrual syndrome: weight, abdominal swelling, and perceived body image.

One hundred forty-eight menstrual cycles were studied in 52 women, and in each cycle various parameters were measured to determine an objective means of assessing the syndrome. Daily mood assessment, body weight, plasma 17 beta-estradiol levels, and plasma progesterone levels were measured. The abdominal dimensions were measured in the lateral and anteroposterior diameters at the level of the umbilicus and 10 cm below; at the same time the same dimensions were measured as perceived by the patient. Mood score showed a marked increase during the premenstrual phase of each cycle. The symptom of bloatedness was marked during the premenstrual phase of the cycle. Despite these highly elevated scores for bloatedness there was no increase in body weight or the measured body dimensions in any plane. However, the patient's perception of body size did increase, and the discrepancy between the perceived body size and the actual body size (perception error) was significant.