Epidural Analgesia in Labour and Risk of Caesarean Delivery

Abstract

Background: A Cochrane Systematic Review of randomised controlled trials of epidural analgesia compared to other or no analgesia in labour reported no overall increased risk of caesarean section. However, many trials were affected by substantial noncompliance and there are concerns about the external validity of some trials for contemporary maternity populations. We aimed to explore the association between epidural analgesia in labour and caesarean section in clinical practice and compare with findings from randomized controlled trials. Methods: Population-based cohort of pregnant women (n=172,785) without major obstetric complications who delivered a singleton live infant in hospitals in New South Wales, Australia, 2007-2010. Data were obtained from linked, validated population-based data collections. Propensity score matching was used to analyse the association between epidural analgesia in labour and caesarean section. Results: Epidural analgesia in labour was used by 54,668 (31.6%) women and 15,926 (9.2%) had a caesarean section. Epidural analgesia in labour was associated with increased risk of caesarean section (RR 2.63; 95% CI [2.53, 2.74]). The association with epidural analgesia in labour is higher for caesarean section for failure to progress (RR 3.09, 95% CI [2.94, 3.25]) than for caesarean section for fetal distress (RR 1.96, 95% CI [1.83, 2.09]). Conclusions: In practice, epidural analgesia in labour is associated with caesarean section in a large maternity population. Population-based studies contribute important information about obstetric care, when research settings and participants may not represent the clinical settings or broader population in which obstetric interventions in labour are applied.