In a multicenter, randomized clinical trial, 282 women who underwent abdominal or vaginal hysterectomy were given a single preoperative 2 g dose of cefotetan (171 evaluable patients) or three perioperative 2 g doses of cefoxitin (84 evaluable patients) as antibiotic prophylaxis. A successful clinical response occurred in 92 percent of those receiving cefotetan and 90 percent of those receiving cefoxitin who underwent abdominal hysterectomy, and in 94 percent of those receiving cefotetan and 93 percent of those receiving cefoxitin who underwent vaginal hysterectomy. The incidence of vaginal cuff cellulitis was 3.4 percent and 5 percent for cefotetan and cefoxitin patients, respectively, who underwent abdominal hysterectomy, and 4.8 percent and 4.5 percent, respectively, for those who underwent vaginal hysterectomy. The incidence of major wound infection was 3.4 percent and 2.5 percent for cefotetan and cefoxitin, respectively, in the abdominal hysterectomy group. Postoperative changes in oral body temperature, duration of hospitalization, and postoperative grading of surgical wounds were similar. Both drugs were well tolerated. These results suggest that a single dose of cefotetan is equally effective and as safe as multiple-dose cefoxitin for prophylaxis in patients undergoing hysterectomy.