A clinical study on abnormal S/D ratio of umbilical artery flow

Objective To evaluate value of systolic peak/ diastolic peak(S/D) ratio of umbilical artery flow in Doppler ultrasonography in predicting fetal hypoxia in pregnancy.Methods 3 020 pregnant women with 28~42 weeks of gestation were examined with color Doppler for frequency spectrum of umbilical artery flow and S/D ratio.388 pregnant women with abnormal S/D ratio of≥3 were included in the study group and 2 632 pregnant women with S/D3 were included in the control group.The pregnancy outcomes and delivery patterns were analyzed.Results The incidences of umbilical cord around fetal neck,moderate and severe hypertensive disorder complicating pregnancy,fetal distress,intrauterine fetal growth retardation(FGR) were significantly higher in the study group than those in the normal control group(u=7.46,3.58, 3.45,4.12,3.46,2.96,6.89 respectively,all P0.01),and in delivery patterns there was significant difference between the two groups(u=6.51,3.46, 2.74 respectively,all P0.01.Conclusion The fetal umbilical artery blood flow is decreased and this affect blood supply of the fetus and placenta,presenting with an abnormal S/D ratio,and the delivery patterns of the pregnant women.