Prophylactic Antibiotics After Cesarean

The investigators propose the conduction of a prospective, randomized, double-blinded clinical trial to evaluate an alternative prophylactic regimen for the prevention of surgical site infection in women who are obese and have been laboring prior to their Cesarean section. This study is to be conducted by the Department of Obstetrics \& Gynecology at John Sealy Hospital at the University of Texas Medical Branch in Galveston, Texas. The intervention being studied will be the administration of cephalexin and metronidazole post-operatively for 48 hours. The primary outcome measure will be surgical site infection (including superficial or deep incisional surgical site infection, endometritis, and other related infections, such as septic pelvic thrombophlebitis and abdominal or pelvic abscess) in the post-operative period. In order to most effectively and accurately analyze our primary and secondary research outcomes, the investigators will standardize our surgical operation techniques in all ways feasible. These recommendations will be in concordance with American College of Obstetrics and Gynecology recommendations, as those generally accepted in the medical literature. All patients will undergo surgery in the same small group of HEPA-filtered and positive air-pressure operating rooms. Appropriate limitations on number of surgeons and assistants scrubbed for surgery, as well as general OR traffic, will be enforced. Patients will undergo hair clipping of the incision site when appropriate. Chlorhexidine skin decontamination will be the standard surgical site preparation. An adhesive drape will be used. Prior to skin incision, cefazolin and azithromycin will be administered. All patients to be considered for recruitment to this study will be undergoing delivery at John Sealy Hospital at the University of Texas Medical Branch in Galveston, Texas. Patients with an elevated BMI \>or =30 kg/m2 who undergo cesarean section after laboring will be considered for randomization either prior to delivery or in the first 7 hours after delivery, to accommodate the need for the first dose of study medication or placebo 8 hours after surgery. Only patients who agree to inclusion after informed consent will be randomized per protocol.