The advantage of antibiotic prophylaxis using a single dose of 2 g of cefotetan, administered during the induction of anesthesia, was studied in 71 patients undergoing an abdominal hysterectomy and presenting at least one of the following risk factors: obesity or procedure exceeding two hours. After random selection, 33 patients were treated, 38 were not and constitute the reference group. Comparison between the two groups shows a significant difference concerning the general morbidity, post-operative fever, urinary infection and abdominal wall abscess. Considering the excellent tolerance of the treatment and the fact that it is easy to use and inexpensive, antibiotic prophylaxis with cefotetan is quite interesting for this type of surgery.