Postterm pregnancy after previous cesarean section.

In order to assess the current management of, and to develop a management scheme for, patients with postterm pregnancy and previous cesarean section (C/S), a retrospective analysis of 112 patients was done. All patients with postdates pregnancy and previous C/S were followed in a postdates clinic according to a previously published protocol. Thirty-four patients (30.4%) underwent elective repeat C/S, and 78 (69.6%) were permitted a trial of labor (TOL). Of these TOL patients, 57 (73.1%) delivered vaginally. Sixteen (42.2%) of 37 patients with a history of prior C/S for cephalopelvic disproportion delivered vaginally. Excluding 34 patients who underwent elective repeat C/S, the remaining 41 patients who had previous C/Ss for other indications delivered vaginally. This difference was statistically significant (p less than 0.001). Other factors--the number of previous vaginal deliveries, type of previous-C/S incision, the complications of the prior C/S and the interval since the previous C/S occurred--had no effect on vaginal delivery. There was no marked difference in perinatal morbidity between infants delivered vaginally and those delivered abdominally. The maternal morbidity, in terms of postpartum fever and requirement for transfusion, in patients with repeat C/S was significantly higher than that in women with vaginal deliveries. Postdates pregnancy was not associated with an increased risk of uterine rupture. On the basis of this experience we think that postterm pregnancy should not be considered a contraindication to a TOL.