Antepartum fetal heart testing: a clinical appraisal

A prospective noncomparative study was designed to test the ability of the nonstress test (NST) and the contraction stress test or oxytocin challenge test (CST/OCT) to predict neonatal morbidity or impending mortality. Two hundred nine pregnancies tested within eight days of delivery were studied. The only two perinatal deaths occurred in association with the postmaturity syndrome, and both had a preceding reactive NST. Some patients (37.5%) with a positive CST/OCT had fetal distress in labor. Ninety-six percent of infants with distress in labor had an antecedent reactive NST. In the study, 25.8% of the patients had a major antepartum, intrapartum, or postpartum complication that was not predicted by the NST. Therefore, electronic antepartum fetal heart rate surveillance was used as only one facet of the overall patient analysis. Management of patients was based upon the combination of antepartum monitoring, real-time ultrasound evaluation of amniotic fluid, and placental morphology, as well as the clinical suspicion of increased risk (using fetal activity testing, etc).