Maternal and neonatal outcomes associated with induction of labor after one previous cesarean delivery: A French retrospective study

BACKGROUND: The safety of methods of labor induction in women with previous cesarean deliveries is still debated. We investigated perinatal outcomes associated with labor induction among women with a trial of labor after one cesarean delivery. METHODS: This retrospective study included 339 women with a trial of labor after one prior cesarean and a singleton term fetus in cephalic presentation in 2013–2016 in a French maternity unit. Labor induction was performed with oxytocin, artificial rupture of membranes and/or prostaglandin E2, according to the Bishop score. The primary outcome was a composite of uterine rupture, low Apgar score, neonatal resuscitation or admission to a neonatal unit. The secondary outcomes included cesarean delivery after onset of labor, postpartum hemorrhage and maternal hospital stay after delivery. We used logistic regression to estimate odds ratios adjusted (aOR) for potential confounders. RESULTS: In our sample, 67.3% of women had spontaneous labor and 32.7% were induced. More than half of the women received oxytocin during labor regardless of the mode of labor. The proportions of the composite outcome and of cesarean after onset of labor were higher in the induced group compared to the spontaneous group (26.1% vs 15.8%, p = 0.02 and 45.0% vs 27.6%, p<0.01, respectively). There were 9 uterine ruptures (2.6%) and this proportion was higher in the induced group compared to the spontaneous group, although this difference was not statistically significant (3.6% vs 2.2%, p = 0.48). After adjustment, labor induction was associated with higher risks of the composite outcome (aOR = 2.45, 95% CI: 1.29–4.65), cesarean after onset of labor (aOR = 2.06, 95% CI: 1.15–3.68) and maternal hospital stay after delivery ≥6 days (aOR = 6.20, 95% CI: 3.25–11.81). No association was found with postpartum hemorrhage. CONCLUSION: Labor induction after one prior cesarean was associated with a higher risk of adverse perinatal outcome. Nevertheless, the higher proportion of uterine rupture did not differ significantly from that in the spontaneous labor group.