Long-term rectal temperature measurements in a patient with menstrual-associated sleep disorder

The international classification of sleep disorders has proposed menstrual-associated sleep disorder. However, few studies have investigated its pathophysiological mechanism. A 34-year-old woman complaining of insomnia in the late luteal phase underwent continuous rectal temperature measurements and simultaneous actigraphic monitoring for 146 days. The acrophase of rectal temperature rhythm was delayed in the luteal phase, compared with that in the follicular phase. Her bedtime and risetime did not differ across the menstrual cycle. These results suggest that her insomnia in the luteal phase may have been a consequence of desynchronization between her temperature rhythm and sleep phase in the luteal phase.