Purpose: to compare the efficacy of tinidazole and cefazolin on the prophylaxis of the febrile and infectious morbidity after vaginal or abdominal hysterectomy. Methods: A randomized clinical trial carried out at the Women's Integrated Healthcare Center (CAISM)/UNICAMP, Campinas, Brazil. Women undergoing to total vaginal or abdominal hysterectomy were randomly enrolled into one of these three groups of antibiotic prophylaxis: tinidazole, cefazolin or an association of both.