[Autonomic nervous system activity during the normal menstrual cycle]

Body adaptation reactions to changes of the internal conditions (neurohumoral shifts related to ovulation and corpus luteum development) were studied in 15 women of a reproductive age with normal biphasic cycle in the early follicular and medium lutein phases on the basis of mathematical analysis of heart rhythm, a number of cardiovascular and respiratory system parameters, and brain electric activity. Moderate tension of the regulatory mechanisms in the lutein phase of the cycle was protective and adaptive and probably related to body preparation to a would-be pregnancy. These adaptive effects are different in different women: in some internal environment parameters vary within a wide spectrum, in others these parameters show a trend to retain their functioning regimen.