High nocturnal body temperatures and disturbed sleep in women with primarydysmenorrhea

Primary dysmenorrhea is characterized by painful uterine cramps, near and d uring menstruation, that have an impact on personal life and productivity. The effect on sleep of this recurring pain has not been established. We com pared sleep, nocturnal body temperatures, and hormone profiles during the m enstrual cycle of 10 young women who suffered from primary dysmenorrhea, wi thout any menstrual-associated mood disturbances, and 8 women who had norma l menstrual cycles. Dysmenorrheic pain significantly decreased subjective s leep quality, sleep efficiency, and rapid eye movement (REM) sleep but not slow wave sleep (SWS), compared with pain-free phases of the menstrual cycl e and compared with the controls. Even before menstruation, in the absence of pain, the women with dysmenorrhea had different sleep patterns, nocturna l body temperatures, and hormone levels compared with the controls. In the mid-follicular, mid-luteal, and menstrual phases, the dysmenorrheics had el evated morning estrogen concentrations, higher mean in-bed temperatures, an d less REM sleep compared with the controls, as well as higher luteal phase prolactin levels. Both groups of women had less REM sleep when their body temperatures were high during the luteal and menstrual phases, implying tha t REM sleep is sensitive to elevated body temperatures. We have shown that dysmenorrhea is not only a disorder of menstruation but is manifest through out the menstrual cycle. Furthermore, dysmenorrheic pain disturbs sleep, wh ich may exacerbate the effect of the pain on daytime functioning.