Oxytocin use during a trial of labor in patients with previous cesarean section.

In patients who have had a previous cesarean section (C/S), the use of oxytocin during a trial of labor (TOL) remains controversial. In order to better delineate the risks associated with oxytocin usage in patients with prior C/S undergoing a TOL, a retrospective investigation was undertaken. During the study period, January 1 to December 31, 1980, 308 previous-C/S patients underwent a TOL. Oxytocin was used on 58 (18.8%) for either labor induction (12) or augmentation (46). Vaginal delivery was accomplished in 31 (53.4%) of the patients who received oxytocin. Vaginal delivery was accomplished in 196 (83.8%) of the 292 patients who labored spontaneously. Patients who had no vaginal deliveries after previous C/S and required oxytocin were at a significantly increased risk of undergoing C/S. There was no statistically significant difference between the oxytocin vs. nonoxytocin groups with regard to instruments used in vaginal delivery, uterine scar dehiscence, transfusions, birth trauma or neonatal outcome. In patients with a previous C/S who undergo a TOL, the use of oxytocin in a judicious manner appears to be safe. However, additional studies are required to corroborate this conclusion.