Labor induction for planned vaginal delivery in patients with previous cesarean section.

The role of labor induction in patients scheduled for vaginal delivery following a previous lower segment cesarean section has been controversial. In Hong Kong, we have managed these patients by induction when there were obstetric or medical indications. A review of 137 patients who had labor induced for a trial of scar showed that induction of labor was a safe procedure and the rate of repeat caesarean section in these patients (18.2%) was similar to that in other patients with a trial of scar who had spontaneous onset of labor (12.9%). There were no serious maternal or fetal complications. Although the use of oxytocin in addition to amniotomy produced no difference in the outcome, we felt that it was useful in preventing a long induction delivery interval as well as avoiding a high failure rate of induction. We conclude that in patients selected for a trial of scar, planned induction of labor should be attempted when an indication for delivery arises, as a high proportion (more than 80%) of these patients gave birth vaginally. If induction were ruled out, most of these patients would have to be delivered by repeat cesarean section, with its associated morbidity and expense.