Abstract

PIP: A set of physiological variables were studied in 5 healthy women having spontaneous menses to determine menstrual cycle modifications of circadian rhythms. Data were gathered at 4-hour intervals over 24 hours on Days 1, 8, 15, 22, and 29 of menses. The acrophases of the menstrual rhythms for the various parameters were as follows: rectal temperature, Day 23; skin reactivity to histamine, Day 30; urinary water, Day 21; estrogens, Day 19; pregnanediol, Day 20; 17-hydroxycorticosterone (17-OH CS), Day 19. Menstrual variations in the timing of the circadian acrophase were also found for urinary 17-OHCS, 17-ketosterone, and potassium as well as for pain threshold and skin reaction to histamine. These results suggest that the adrenal gland and ovary are phased by the menstrual cycle.