Objective measurement of hot flushes associated with the premenstrual syndrome

Because the majority of women with PMS complain of sweats and chills resembling menopausal flushes, we attempted to document the physiologic changes during these episodes. A 26-year-old nulliparous woman with PMS described the occurrence of hot flush-like episodes coincident with PMS symptoms. The patient completed prospective self-rating scales for two consecutive cycles to establish the pattern and severity of PMS. On day 26 of the first cycle when PMS symptom scores were elevated, continuous monitoring of skin resistance and finger temperature and frequent blood sampling for LH were performed for 8 hours. The patient experienced five flush episodes, each of which was associated with a drop in skin resistance of up to 4000 ohms and was coincident with an LH pulse. Three of the flushes were associated with a rise in finger temperature of up to 10 degrees C. These physiologic changes are identical to those seen during menopausal flushes and suggest that PMS may be associated with neuroendocrine events typical of E withdrawal.