Vaginal birth after caesarean section versus elective repeat caesarean section: assessment of maternal downstream health outcomes.

OBJECTIVE: To compare the maternal implications of strategies of vaginal birth after caesarean section (VBAC) attempt versus elective repeat caesarean section in women with one previous lower segment caesarean section.

DESIGN: Decision model.

POPULATION: Women with one prior low transverse caesarean section who are eligible for trial of labour.

METHODS: Two decision models were built: the first one applying to women planning only one more pregnancy, the second one applying to women planning two more pregnancies. Probability estimates for VBAC success rate and risks of uterine rupture, placenta praevia, placenta accreta and hysterectomy were extracted from the available literature.

MAIN OUTCOME MEASURES: Hysterectomy for uterine rupture, placenta accreta or other indications.

RESULTS: In the first model VBAC attempt led to a higher hysterectomy rate (267/100,000) compared with repeat caesarean section (187/100,000). However, in the second model a policy of elective repeat caesarean section led to higher cumulative hysterectomy rate: 1465/100,000 versus 907/100,000 for VBAC. The first model was robust to all but one variable in sensitivity analyses. The second model was robust to all variables in sensitivity analyses.

CONCLUSIONS: These results indicate that long term reproductive consequences of multiple caesarean sections should be considered when making policy decisions regarding the risk-benefit ratio of VBAC.