Utility of Intrapartum Fetal Heart Rate Monitoring in a Contemporary Labor and Delivery Unit [4Q

Abstract

INTRODUCTION: To evaluate the use of intrapartum electronic fetal heart rate monitoring (EFM) as a screening tool for adverse neonatal outcomes. METHODS: This is a retrospective study of 16,980 term, singleton deliveries at a single hospital from 2013-2014. Cases of adverse neonatal outcomes were compared to unaffected controls by the following predictor variables: late, variable, early, and prolonged decelerations; accelerations; tachycardia; bradycardia; and minimal variability. The primary outcome was a composite adverse outcome comprised of five-minute Apgar score less than 4, umbilical arterial pH less than 7.0, sepsis, seizures, encephalopathy, and respiratory failure. Secondary outcomes were neonatal intensive care unit (NICU) admission, hypoxia, hypoglycemia, pH less than 7.0, seizures, and abstinence syndrome. Independent associations were ascertained using logistic regression. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for significant parameters. RESULTS: For the composite adverse outcome, prolonged decelerations were positively (OR 2.19) and accelerations were negatively (OR 0.044) associated. For NICU admission, associations included prolonged (OR 1.24) and late (OR 1.39) decelerations, minimal variability (OR 1.17), and tachycardia (OR 1.81). Neonatal hypoxia (OR 0.076), hypoglycemia (OR 0.21) and seizures (OR 0.005) were all negatively associated with accelerations. Low five-minute Apgar score was positively associated with prolonged decelerations (OR 8.69). For the composite adverse outcome, prolonged decelerations had sensitivity, specificity, PPV, and NPV of 0.372, 0.657, 0.00606, and 0.995, while for absence of accelerations were 0.0185, 0.998, 0.0357, and 0.996, respectively. CONCLUSION: Standard EFM parameters have excellent NPV but poor PPV when used intrapartum to screen for adverse neonatal outcomes.