Predictors of Expedited Delivery in the Presence of Severe Fetal Acidemia (Umbilical Cord Arterial pH <7) [30O

Abstract

INTRODUCTION: The purpose of this study was to determine which characteristics of EFM in babies with severe acidemia (umbilical cord arterial pH <7) affected whether delivery was expedited or not. METHODS: A retrospective cohort study was performed on babies with umbilical cord arterial pH <7. Two groups were identified: (1) expedited delivery (either operative vaginal delivery or urgent/emergent cesarean section) and (2) non-expedited delivery (spontaneous vaginal delivery, scheduled or non-urgent cesarean section). The last hour of EFM was reviewed. Maternal, labor, and neonatal characteristics between the groups were compared using Chi-squared test for independence and the Fisher's Exact Test. IRB approval obtained. RESULTS: Thirty neonates with umbilical cord pH <7.0 were identified. Of these, 47% were delivered in expedited fashion. There was no statistical difference between groups in average umbilical cord arterial pH or base excess, gestational age, if labor was induced, length of labor, Pitocin usage for labor augmentation, sentinel events, 5 minute Apgar score or neonatal length of stay. Recurrent late decelerations were more likely to be present in the expedited delivery group (31% vs. 0%), while moderate variability (100% vs. 69%), accelerations (77% vs. 31%), and category I tracing (46% vs. 8%) were more common in the non-expedited group. CONCLUSION: In babies born with umbilical arterial pH of <7, expedited delivery was more common in the presence of recurrent late decelerations during the last hour of fetal monitoring. A Category I fetal heart tracing, moderate variability, and accelerations were more common when the delivery was not expedited.