Progesterone levels and sleep-related breathing during menstrual cycles of normal women.

The respiratory stimulant effect of progesterone has been known for many years and has led to the hypothesis that this hormone protects young, premenopausal women from disordered breathing and apnea during sleep. Therefore, sleep, breathing, and gonadal hormone parameters were evaluated for 11 normal, menstruating women during times of high and low progesterone levels. No sleep or breathing parameter changed significantly with varying levels of progesterone. Although normal women show a significant change in progesterone levels across the course of the menstrual cycle, the levels achieved did not produce significant changes in breathing parameters.