LAUSR

Introduction: Epidural analgesia (EA) is the most widespread pharmacologic method of labor pain relief. There remains disagreement, however, regarding its adverse effects. The objective of this study was to determine the effect of EA administration on the risk of cesarean delivery and its causes (e.g., stalled labor, risk of loss of fetal well-being, among others) and the degree to which this effect may be modulated by mother-, newborn-, and labor-related variables. Method: A retrospective cohort observational study was conducted including all deliveries in a Spanish public hospital between March 2010 and March 2013 (N = 2,450; EA = 562, non-EA = 1,888). Results: Risk of a cesarean section was significantly increased by EA administration (odds ratio [OR] = 2.673; p < .0001). The percentage of cesarean deliveries due to the risk of loss of fetal well-being was significantly higher in the EA (47.8%) versus non-EA group (27.5%; OR = 1.739; p = 0.0012,). The EA-associated risk of cesarean section was not significantly modified as a function of maternal age or parity, fetal position, newborn weight, weeks of gestation, or sedation administration alone. However, these variables in combination may increase the risk. We present multivariate models for each group that account for these variables, allowing for estimation of the risk of a cesarean delivery if EA is administered. Conclusion: EA is associated with an increased risk of cesarean delivery. Other variables in combination (maternal age or parity, fetal position, newborn weight, weeks of gestation, or sedation administration) may increase this risk.