ln 484 cases of high risk pregnancy

the systolic and diastolic ratios (S/D) of umbilical arterial blood flow were measured with Doppler ultrasound. Non - atress tests (NST) were carried out sumultaneously. Abnormal results were found in 178 cases. The incidence of abnormal CST in abnormal S/D group (111 case.) was 41.4%

which was significantly higher than that (26.2 % ) of ubnormal NST gruup (42 cases) P< 0.05 However

the incidence of low Apgar scores (< 7) at one and five minutes was higher in the abnormal NST group than that with abnormal S/D group. P<0.05. The incidence of abnormal CST reaults and low Apgar scores at one and five minutes was highest in those (25 patients) with both abnormal S/D and abnormsl NST.P<0.001. The incidence of fetal distress or amniotic fluid stained with meconium at delivery has no difference among all these groups P>0.05. The results show that prenatal monitoring with umbilical artery velocity waveform could provide an early signal of fetal compromise.