A double-blind, prospective study over a 12-month period evaluated the effectiveness of cefazolin and cephalexin in reducing infection and morbidity in private patients undergoing vaginal and abdominal hysterectomy. Prophylactic antibiotics reduced febrile morbidity from 74.4% to 20.8% in the vaginal group and from 46.2% to 24.0% in the abdominal group. Serious postoperative infections such as pelvic abscess, pelvic cellulitis and abdominal wound infection were reduced from 11.5% to 0% in the abdominal group and from 32.6% to 2.1% in the vaginal group. The use of prophylactic antibiotics was of benefit in the perimenopausal and postmenopausal patient, as well as in the premenopausal patient, although, in some categories, the numbers were too small to be statistically significant.