Objective: To determine the role of umbilical artery Doppler velocimetry in the management of oligohydramnios.
Study design: In a retrospective chart review covering a two-year period, pregnancies with oligohydramnios evaluated by Doppler velocimetry of the umbilical artery were identified. Those patients with ruptured membranes and complex congenital anomalies were excluded from analysis. In the remainder, various measures of perinatal morbidity, including delivery of a small-for-gestational-age infant, preterm delivery, hyperbilirubinemia, requirement for blood transfusion, and other cardiovascular or pulmonary complications, were correlated with recorded values of the systolic/diastolic (S/D) ratio.
Results: Seventy-six subjects were identified for study. Forty-six had normal S/D ratios; 17 (37%) were associated with identifiable perinatal morbidity. When prematurity due to delivery for the sole indication of oligohydramnios was excluded, morbidity occurred in five patients (11%). Conversely, of the 30 patients with abnormal Doppler indices, 80% had an adverse outcome.
Conclusion: Pregnancies with oligohydramnios and normal umbilical artery Doppler velocimetry were significantly (P < .001) less likely to experience an abnormal perinatal outcome as compared to those with abnormal Doppler indices. An elevated S/D ratio identified an increased risk of an adverse perinatal outcome in women with oligohydramnios. Avoiding intervention in pregnancies with oligohydramnios and normal umbilical artery Doppler velocimetry may decrease iatrogenic morbidity due to prematurity by as much as 26%.