Perioperative antibiotic prophylaxis is cesarean section.

The effect of an 8-hour, 3-dose perioperative regimen of cefazolin or placebo was evaluated in 97 patients. Postoperative morbidity occurred in 13 patients (27.1%) in the cefazolin group and in 17 patients (34.7%) who received placebo. The clinical sites of infection were similar in both groups except that wound infections (2) and sepsis (2) were found only in patients receiving placebo. Aerobic organisms diminished and anaerobes increased in patients who received antibiotics. Aerobic isolates were essentially unchanged and fewer anaerobes were recovered from patients given placebo. Antibiotic levels observed at cesarean section were in the therapeutic range. The only risk factor which correlated with morbidity was the presence of ruptured membranes. This short course, single drug regimen did not significantly reduce morbidity although it was bacteriologically effective.