Single-dose antibiotic prophylaxis in high-risk patients undergoing cesarean section. A comparative trial.

A prospective, double-blind study was performed to evaluate the comparative efficacy of single- and multiple-dose antimicrobial prophylaxis for preventing infection in high-risk patients undergoing cesarean section. One hundred fifty-eight patients were randomly assigned to receive either a single perioperative dose of mezlocillin, three doses of mezlocillin or three doses of cefoxitin. The incidence of endometritis was 5.9%, 4.0% and 4.0%, respectively. The incidence of febrile morbidity was 5.9%, 2.0% and 6.1%, respectively. These differences are not statistically significant. The single perioperative dose of mezlocillin was as effective as the three-dose regimen of either mezlocillin or cefoxitin.