Sympatho-vagal activities during the menstrual cycle of eumenorrheic women with premenstrual symptomatology

A majority of menstruating women experience a cyclic recurrence of a constellation of various symptoms in the premenstrual phase. The etiopathogenesis of the phenomenon, however, remains unknown. The present study was designed to evaluate whether the activity of the autonomic nervous system (ANS), which modulates a human's internal environment, is altered during the menstrual cycle of women with premenstrual symptomatology. Thirty healthy young women participated in this study. All subjects were investigated during the follicular and late luteal phases. The ANS activity was assessed by means of heart rate variability power spectral analysis during supine rest. The ANS activity significantly changed in the symptomatic late luteal phase from the non-symptomatic follicular phase only in women who experienced substantial increase (> 20%) in diverse symptoms premenstrually. In addition, the women of this group possessed higher sympathetic nerve activity and lower parasympathetic nerve activity in the late luteal phase compared with the women who experienced less premenstrual symptomatology. The ANS activity in the follicular phase did not differ among the subjects regardless of their premenstrual symptoms. The present study suggests that the altered functioning of ANS in the late luteal phase could be associated with diverse psychosomatic or behavioral symptoms appearing premenstrually.