UMBILICAL ARTERY DOPPLER VELOCIMETRY VS THE NONSTRESS TEST AS A PREDICTOR OF POOR OUTCOME IN HIGH-RISK PREGNANCIES - OLIGOHYDRAMNIOS VS NORMAL AMNIOTIC-FLUID

Objective: We prospectively compared umbilical artery Doppler velocime try and the nonstress test as predictors of adverse perinatal outcome in pregnancies complicated by oligohydramnios, drawn from a general hi gh-risk population. Methods: Thirty patients with oligohydramnios and 150 patients with normal amniotic fluid indices were recruited from re ferrals for antepartum fetal testing. All subjects had good obstetrica l dating and consented to the institutionally approved protocol. Nonst ress testing, umbilical artery Doppler velocimetry, and amniotic fluid index determinations were performed on each subject at the same sitti ng. Adverse perinatal outcome was defined as the presence of meconium- stained amniotic fluid, delivery for fetal distress, 1- or 5-minute Ap gar scores <7, arterial cord pH <7.20, neonatal resuscitation requirin g intubation or positive pressure ventilation, neonatal intensive care admission, delivery of a growth-retarded infant, or perinatal death. Results: The nonstress test offered significantly better sensitivity i n detecting adverse outcomes than the systolic/diastolic ratio in pati ents with (60% vs 10%, P < 0.0001) and without (26% vs 7%, P < 0.001) oligohydramnios. No differences were noted in the tests' specificities , or positive and negative predictive values. Conclusions: In our gene ral high-risk population, the nonstress test appears to be a better st and-alone screen than the systolic/diastolic ratio, regardless of amni otic fluid volume.