Intrapartum temperature elevation, epidural use, and adverse outcome in term infants

Objective: To examine the association of intrapartum temperature elevation with adverse neonatal outcome among low-risk women receiving epidural analgesia, and evaluate the association of epidural with adverse neonatal outcome without temperature elevation. Methods: We studied all low-risk nulliparous women with singleton pregnancies ≥37 weeks delivering at our Hospital during the year 2000, excluding pregnancies where infants had documented sepsis, meningitis, or a major congenital anomaly. Neonatal outcomes were compared between women receiving (n=1538) and not receiving epidural analgesia (n=363) in the absence of intrapartum temperature elevation (≤99.5°F), and according to the level of intrapartum maternal temperature elevation within the group receiving epidural (n=2784). Logistic regression was used to evaluate neonatal outcome while controlling for confounders. Results: Maternal temperature >100.4°F developed during labor in 19.3% (537/2784) of women receiving epidural analgesia compared to 2.4% (10/425) not receiving epidural (P<.0001). In the absence of intrapartum temperature elevation (≤99.5°F), no significant differences were observed in adverse neonatal outcomes between women receiving and not receiving epidural. Among women receiving epidural, a significant linear trend was observed between maximum maternal temperature and all neonatal outcomes examined including hypotonia, assisted ventilation, 1 and 5 minute Apgar scores <7, and early-onset seizures. In regression analyses, infants born to women with fever >101°F had a 2-6 fold increased risk of all adverse neonatal outcomes examined. Conclusions: The proportion of infants experiencing adverse outcomes increased with the degree of epidural-related maternal temperature elevation. Epidural use without temperature elevation was not associated with any of the adverse outcomes we studied.