PHYSIOLOGIC CRITERIA OF OBSTETRIC RISK: EARLY PROGNOSIS FOR PREGNANCY OUTCOME BASED ON MATERNAL CARDIORHYTHM VARIABILITY

Aim: to investigate the early (up to 26 wks.) prognosis for low and moderate-risk pregnancy outcome based on maternal heart rate variability (HRV) with addition of umbilical cord artery Doppler taking into account patterns of autonomic regulation in women’s organism. Material and methods. 79 somatically healthy women with uncomplicated pregnancies (control, Con), and 62 women with different forms of gestational pathology (GP group: preeclampsia, intrauterine growth restriction, labor abnormalities and miscarriage) are examined. Mean women’s age and gestational time at the moment of exam were 23.4 ± 3.7 yrs and 20.8 ± 2.9 wks (M ± SD) respectively; the percentage of primiparas was roughly equivalent in Con and GP groups, 69.0 % and 71.2 % respectively. There were analyzed 1) spectral types of maternal HRV, which characterize pattern of autonomic regulation; 2) the detrended fluctuation analysis (DFA) parameter as an index of heart rate non-linear dynamics and 3) umbilical cord artery Doppler (diastolic blood flow indices, DBIua). Results. DFA decrease in dynamics of maternal moderate voluntary hyperventilation (not more than 1.5 of respiratory minute volume determined at rest) appeared to be typical for GP group in persons with increased sympathetic and/or baroreflective activity (GP: 61.4 %; Con: 6.2 %; p < 0.001). Pretest odds of gestational pathology by Bayesian criterion enhanced after testing in these subgroups 9.9-fold (0.614/0.062). Combined DBIua/DFA testing was found to be much more informative for subgroups of women with optimal and vagotonic regulation, yielding 3.5-fold (0.938/0.028) raise of pretest odds on gestation pathology. Conclusion. Combination of DFA testing with diastolic blood flow indices in umbilical cord artery under maternal moderate voluntary hyperventilation is informative for early prognosis of pregnancy outcome in women with different neuroautonomic patterns.

Kleshchenogov S.A. – candidate of medical sciences, senior researcher, e-mail: serg_kle29@mail.ru