Is epidural analgesia during labor related to retained placenta?

Abstract

To explore the influence of epidural analgesia on the course of the third stage of labor and on the incidence of the complete retained placenta as well as retained parts of the placenta. This is a population-based cohort study in a tertiary medical center. We collected data from all 4227 spontaneous singleton vaginal deliveries during 6 months and compared the incidence of retained placenta in deliveries with epidural analgesia with those without analgesia. Multivariable logistic regression was used to control for possible confounders. More than two-thirds of the women (69.25%) used epidural analgesia during their delivery. A need for intervention due to placental disorder during the third stage of labor was noted in 4.2% of all deliveries. Epidural analgesia appeared to be significantly (P=0.028) related to placental disorders compared with no analgesia: 4.8% vs. 3%, respectively. Deliveries with manual interventions during the third stage, for either complete retained placenta or suspected retained parts of the placenta, were associated with the use of epidural analgesia (P=0.008), oxytocin (P=0.002) and older age at delivery (P=0.000), but when including all factors in a multivariable analysis, using a stepwise logistic regression, the factors that were independently associated with interventions for placental disruption during the third stage of delivery were previous cesarean section, oxytocin use and, marginally, older age. Complete retained placenta and retained parts of the placenta share the same risk factors. Epidural analgesia does not directly influence the incidence of complete retained placenta or retained parts, though clinically linked through increased oxytocin use. The factors that were independently associated with interventions for placental disruption during the third stage of delivery were previous cesarean section, oxytocin use and older age.