Vaginal birth after cesarean: the European experience

Cervical ripening by prostaglandin E2 in patients with a previous cesarean section

OBJECTIVE

To assess the efficacy and safety of prostaglandin in inducing labor in pregnant women with one previous cesarean section. Secondly, to evaluate predictors of successful vaginal delivery in cervical ripening by prostaglandin in these women.

STUDY DESIGN

This was an observational, retrospective, single-center study conducted in a type 3 maternity unit at Bicêtre University Hospital between January 1, 2013 and December 31, 2016. Patients with one previous cesarean section, a singleton pregnancy, a fetus in the cephalic presentation with a medical indication for induction of labor and an unfavorable cervix (Bishop score less than 6) were included in the study. Cervical ripening was performed using a dinoprostone intravaginal device for a duration of 24 h.

RESULTS

A total of 153 patients were included in the study. The rate of vaginal delivery was 55.6 % (85/153) overall and 78.3 % (36/46) in the subgroup of 46 women with a previous vaginal delivery before or after the cesarean section. There was no difference in neonatal and maternal morbidity (defined by intraoperative wounds or postpartum hemorrhage or uterine rupture) and mortality between women who delivered vaginally and women who had a cesarean section. The two cases of complete uterine rupture have been reported for patients whose labor was induced by intravaginal prostaglandin followed by intravenous oxytocin. The total maternal morbidity rate was 11.8 % (n = 8/68) in the case of emergency cesarean section. Predictors of vaginal delivery were a history of vaginal delivery, the onset of labor following cervical ripening, and a higher Bishop score before and after the 24 h following the cervical ripening.

CONCLUSION

Cervical ripening by prostaglandin after previous cesarean delivery has a 56 % success rate, with a 1.3 % risk of uterine rupture, especially when prostaglandin is combined with oxytocin. Low-risk patients should be identified to propose cervical ripening by prostaglandin.

Management of previous cesarean section

PURPOSE OF REVIEW

The management of cesarean sections causes much controversy among healthcare providers, patients, and insurers. A trial of vaginal birth after previous cesarean is reported to be a safe and practical method to reduce the rate of cesarean sections. The popularity of vaginal birth after previous cesarean has increased over the past two decades, but rates have recently started to decline again. This review will evaluate recent literature that might be responsible for this reversal in trend.

RECENT FINDINGS

Earlier studies on previous cesarean section pregnancies focused primarily on the success rate of vaginal birth after previous cesarean, which is reported to be 60-80%. Recent large, retrospective, population-based cohort studies examined the maternal and neonatal safety of trial of labour compared with elective repeat cesarean delivery, and confirmed that the risks of uterine rupture and neonatal mortality were significantly increased after trial of labour, particularly when induced with prostaglandins. However, the absolute risk of adverse events remains small. The maternal and neonatal morbidity risk increases when vaginal birth after previous cesarean attempts fails, which emphasizes the importance of careful case selection.

SUMMARY

Recent studies highlighted the risks of attempted vaginal birth after previous cesareans, especially when trials fail, but have not addressed the long-term risks of an elective repeat cesarean delivery. The assessment of treatment risks by observational studies is subject to bias, because the different treatment groups may not be comparable at the outset. In the absence of better data, the counselling of such women must currently be based on this evidence.