Epidural anaesthesia for labour: does it influence the mode of delivery?

Labor epidural analgesia and the incidence of instrumental assisted delivery

OBJECTIVE

To assess the influence of labor epidural analgesia on the course of labor and to determine its association with instrumental assisted delivery rate.

MATERIALS AND METHODS

A retrospective case-control study was performed during 2007-2011 aiming to identify the relation between epidural analgesia (EA) and instrumental assisted delivery (IAD) rate. All patients in whom instrumental assistance for delivery was applied were allocated into either case (parturients who received EA and had IAD) or control (parturients who did not receive EA but had IAD) groups. Maternal demographic data, pregnancy and delivery characteristics as well as neonatal short-term outcome were studied.

RESULTS

A total of 7675 vaginal deliveries occurred during the study period and 187 (2.43%) patients had IAD. Vacuum extraction was applied to 67 (2.16%) parturients who received EA, and to 120 (2.61%) who did not. The median duration of the first stage of labor was 510 min in the EA group as compared to 390 min in the control group (P=0.001). The median duration of the second stage of labor among cases and controls was 60 and 40 min, respectively (P<0.0005). Cases more often had their labor induced by oxytocin 80.3% as compared to 58.3% among controls (P=0.003). There was no significant association between the use of EA and increased IAD rate (OR=0.81; 95% CI, 0.60-1.09).

CONCLUSIONS

Labor EA did not increase the incidence of IAD and the risk of adverse neonatal outcomes, but was associated with prolonged first and second stages of labor.

Mode of delivery after epidural analgesia in a cohort of low-risk nulliparas

BACKGROUND

  Although epidural analgesia is widespread and very effective for alleviating labor pain, its use is still controversial, as the literature is inconsistent about the risk of adverse birth outcome after administration of epidural analgesia. The aim of this study was to explore associations between epidural analgesia and mode of delivery.

METHODS

  Data were obtained from a prospective cohort from nine Danish labor wards and comprised 2,721 term nulliparous women with spontaneous onset of labor and a singleton fetus in cephalic presentation. Information about epidural analgesia, mode of delivery, and birth complications was obtained by the staff attending labor. Additional information was provided from self-administered questionnaires in gestational week 37. Multiple logistic regression analyses were used to estimate the association between epidural analgesia and birth outcomes. Results are presented as crude and adjusted odds ratios (OR [95% CI]).

RESULTS

  Of the total cohort, 21.6 percent required epidural analgesia, 8.7 percent had emergency cesarean section, and 14.9 percent had vacuum extraction. Women with epidural analgesia had a higher risk of emergency cesarean section (adjusted OR: 5.8; 95% CI: 4.1-8.1), and vacuum extraction (adjusted OR: 1.7; 95% CI: 1.3-2.2). In a subgroup of the cohort with a very low overall risk of cesarean section, 3.4 percent had emergency cesarean section and an increased risk of emergency cesarean section was also found in this group (adjusted OR: 3.5; 95% CI: 1.5-8.2).

CONCLUSIONS

  In nulliparous women of a very low-risk population, use of epidural analgesia for labor pain was associated with higher risks of emergency cesarean section and vacuum extraction.

The effect of epidural analgesia on labor progress and outcome in nulliparous women

OBJECTIVE

The present study was designed to investigate the influence of epidural analgesia on labor progress and outcome in nulliparous women.

METHODS

A population-based study comparing women with and without epidural analgesia was conducted. Deliveries occurred during 1988-2006 at the Soroka University Medical Center. A multivariable logistic regression model with backward elimination was constructed to control for confounders.

RESULTS

During the study period there were 39 498 deliveries; epidural analgesia was given in 9960 (25.2%) of these. Using a multivariable analysis with backward elimination, the following conditions were significantly associated with the use of epidural analgesia: advanced maternal age, oligohydramnios, premature rupture of membranes, induction of labor, and Jewish (vs. Bedouin) ethnicity. These patients were more likely to deliver by cesarean delivery (CD; OR = 1.4, 95% CI 1.3-1.5; p < 0.001) and vacuum extraction (OR = 1.5, 95% CI 1.4-1.7; p < 0.001). After controlling for possible confounders such as macrosomia, failed induction, hypertensive disorders, gestational diabetes, maternal age, labor dystocia, and ethnicity, epidural analgesia was not found to be an independent risk factor for CD but rather a protective factor (OR = 0.9, 95% CI 0.8-0.9; p = 0.038). When vacuum extraction was the outcome variable, epidural analgesia was documented as an independent risk factor (OR = 1.1, 95% CI 1.01-1.3; p = 0.04).

CONCLUSIONS

Epidural analgesia in nulliparous parturients increases the risk for labor dystocia and accordingly is an independent risk factor for vacuum extraction. Nevertheless, it does not pose an independent risk for cesarean delivery.