Vaginal birth after cesarean section: a reappraisal of risk

A three-year retrospective study was performed to assess morbidity associated with an attempted vaginal birth after cesarean section at a tertiary level military obstetric hospital. Examination of delivery records revealed a 61.16% success rate for attempted vaginal births after cesarean sections. Mean birth weights differed significantly between successful and unsuccessful vaginal births after cesarean sections. Infants with birth weights greater than 3720 gm were less likely to be vaginally delivered. Those gravidas with a successful vaginal birth after cesarean section had a significantly higher rate of perineal lacerations, as compared with other vaginal births during the study period. The scar separation rate of 1.79% was significantly higher than the 0.50% rate reported elsewhere. One patient who attempted a vaginal birth after cesarean section required a cesarean hysterectomy after scar separation occurred during labor. There were two perinatal deaths, both of which occurred at greater than 40 weeks' gestation, for a perinatal mortality rate of 8.93/1000 births. Women who consider vaginal birth after cesarean section should be counseled with regard to the increased risk of perineal trauma. Estimates of fetal weight at term should be a part of the decision-making process before vaginal birth after cesarean section is attempted.