UMBILICAL ARTERY DOPPLER VELOCIMETRY AND OXYTOCIN CHALLENGE TEST IN NONREACTIVE NONSTRESS TESTS

Objective: To compare the clinical value of umbilical artery Doppler velocimetry and oxytocin-challenge test (OCT) in predicting perinatal outcome following a nonreactive nonstress test (NST). Methods: Prospective blind study of 250 high-risk pregnancies. All patients were examined by NST and Doppler velocimetry between 28 and 41 weeks. Nonreactive NST was followed by OCT. Outcome was defined as poor if one of the following was present: fetal distress as indication for delivery, birth weight <10th percentile, 5-min Apgar <7, cord pH <7.2, early neonatal death. Results: Doppler velocimetry and NST had similar indices of prediction for perinatal outcome (with a sensitivity of 81.7% and 80% and a specificity of 95.3% and 92.6%, respectively). Doppler and NST were concordant in 79.6% and Doppler and OCT in 95.8%. Doppler and OCT also had identical degrees of prediction. Doppler velocimetry results following a nonreactive NST were highly correlated to OCT results. Conclusions: Separately, Doppler and NST are equally poor predictors of perinatal outcome. When combined, they become a more effective screening tool. Our results also suggest that Doppler velocimetry can possibly be offered instead of OCT to patients with abnormal NSTs to further define fetal status.