OBJECTIVE To identify risk factors for relaparotomy after cesarean delivery. METHODS Cases of exploratory laparotomy at Lis Maternity Hospital, Tel Aviv, Israel, following cesarean delivery between 2000 and 2010 were reviewed retrospectively. Each case in the study group was matched randomly with 5 control cases in which the patient underwent cesarean delivery only. Demographic and clinical data before and during the primary procedure were compared. RESULTS Twenty-eight (0.2%) of 17482 cesarean deliveries were followed by exploratory relaparotomy. Significant differences between the study and the control (n=140) groups were found in: placental abruption as an indication for cesarean (17.8% vs 0.6%; P=0.004); duration of primary operation (45.3 ± 21.1 vs 29.9 ± 11.8 minutes; P=0.007; 95% CI, 5.1-19.2); and experience of chief surgeon (10.1 ± 1.6 vs 5.8 ± 0.4 years; P=0.02; 95% CI, 0.0-5.0). Findings during relaparotomy were: abdominal wall bleeding/hematoma (n=4 [14.2%]); uterine scar bleeding (n=4 [14.2%]); retroperitoneal bleeding (n=1 [3.5%]); adhesions causing bowel obstruction (n=1 [3.5%]); and uterine scar gangrene (n=1 [3.5%]). There were no findings for 17 (60.7%) patients. CONCLUSIONS The incidence of relaparotomy following cesarean was 0.2% (1 per 624 cesarean deliveries). Significant risk factors were placental abruption and longer operative time.