The Joel-Cohen incision followed by nonclosure of pelvic and parietal peritoneum has been advocated as an alternative method to the Pfannenstiel incision with peritonealization at cesarean section. A randomized trial was designed to compare intra- and postoperative morbidity between the two techniques. Women to undergo a cesarean section were randomly allocated to have either the Joel-Cohen incision with the parietal and pelvic peritoneum left open (group 1) or to have the Pfannenstiel incision with both peritoneal layers sutured (group 2). The myometrium was closed with 1-0 polyglactin 910 suture using a continuous single-layer nonlocking technique. Patients in group 2 had the peritoneum approximated with 2-0 polyglactin 910 suture. The fascia was sutured with continuous 1-0 polyglactin 910 suture in all cases. Opening time was defined as the interval from skin incision to the opening of the uterine cavity. Febrile morbidity was defined as a temperature > or =38 degrees C on two occasions 4 hours (hr) apart excluding the first postoperative day. Endometritis was defined as postpartum temperature > or =38 degrees C on two occasions 4 hr apart, with uterine tenderness and/or foul-smelling lochia. One hundred forty-nine and 150 patients were allocated to group 1 and to group 2, respectively. A shorter median (range) opening time [4 min (2-21) vs. 6 min (2-19), respectively, p < 0.01] and a shorter median (range) operative time [30 min (10-65) vs. 40 min (20-110), respectively, p < 0.01] were observed in group 1. No difference was found in terms of intraoperative complications, proportion of patients who required transfusion, endometritis, sepsis, febrile morbidity, and urinary tract infections. A higher rate of wound infections was found in group 2 than in group 1 [14 of 150 (9.3%) vs. 2 of 149 (1.3%), respectively, p < 0.01]. The Joel-Cohen incision without peritonealization resulted in a shorter opening and total operative time than the Pfannenstiel laparotomy with peritonealization. This was accomplished with a reduction of wound infections.