[Comparative study of umbilical artery Doppler velocimetry, antenatal fetal heart rate monitoring and umbilical artery blood-gas analysis in the prediction of neonatal outcome].

One hundred and fifteen term pregnancies (62 normal pregnancies, 53 high risk pregnancies) were observed by umbilical artery Doppler velocimetry (UmA S/D ratio) and antenatal fetal heart rate monitoring (NST), and 37 of them were also observed by umbilical artery blood-gas analysis at birth. We compared the effects of these three methods to predict the neonatal outcome. The standards of the neonatal poor outcome were 5-min Apgar score < or = 7 and/or a birth weight < 2500g (SGA). The results were: (1) The neonatal poor outcome were more frequently observed in the abnormal UmA S/D ratio (> or = 3.0) group and in the UmA pH < or = 7.2 group (P < 0.005, P < 0.025, respectively), but there was no significant difference between the NST reactive or nonreactive groups (P > 0.05); (2) The neonatal acidosis at birth was also associated with the abnormal UmA S/D ratio (> or = 3.0); (3) The sensitivities of UmA S/D ratio, UmA pH, NST to predict the 5-min Apgar score < or = 7 were 60.0%, 60.0%, 20.0% respectively; the specificities 84.6%, 81.3%, 81.8% respectively. And their sensitivies to predict SGA were 100.0%, 100.0%, 40.0% respectively; the specificities 86.4%, 80.0%, 82.7% respectively. Our data show that UmA S/D ratio and UmA pH are better than NST in the prediction of neonatal outcome, and the abnormal UmA S/D ratio is closely associated with neonatal acidosis at birth.