[Pathogenesis of deceleration in the prenatal period]

Comprehensive examination, making use of cardiotocography, dopplerometry, and doppler echocardiography, was carried out to disclose the contribution of fetal hemodynamic disorders to the pathogenesis of antenatal deceleration in 69 pregnant women. Disorders of both intracardiac fetal hemodynamics and of the fetoplacental circulation were revealed in all the cases with deceleration. Therefore, circulatory disorders underlie the pathogenesis of decelerations. The development of decelerations is related to the progressive deterioration of fetoplacental circulation and, specifically, to marked changes in the intracardiac hemodynamics in conditions of augmenting peripheral vascular resistance and hypoxia of the fetus.