The aim of this study is to evaluate the clinical efficiency of perioperative short-term prophylaxis in gynecological surgery, in order to prevent both systemic and local infections, caused either by aerobic or by anaerobic bacteria. A group of 320 patients, undergoing abdominal or vaginal hysterectomy and treated with perioperative antibiotic prophylaxis is compared, with 320 women undergoing conventional wide-spectrum antibiotic treatment from the first post-operative day for 4-5 days.