Core body temperature during menopausal hot flushes

Objective: To measure core body temperature by ingested radiotelemetry pill and rectal temperature during menopausal hot flushes under controlled laboratory conditions. Design: Patients were recorded during sleep using both methods in a sound-proofed, temperature- and humidity-controlled laboratory room. Setting: University medical center. Patients: Eight postmenopausal women who were amenorrheic for greater than or equal to 1 year and reported frequent hot flushes. Results: Thirty-seven hot flushes were detected by criterion increases in sternal skin conductance level. Significant increases in telemetered but not rectal temperature occurred before 24 of the hot flushes. Conclusions: Core body temperature elevations precede a majority of menopausal hot flushes and serve as one trigger of this heat-loss phenomenon.