This study will be conducted over three years with an estimated sample size of 4500 patients. Prior to enrollment of study subjects, each year will be divided into 3-month blocks and each block will be assigned one of the two study antiseptic solutions — 2% chlorhexidine gluconate in 70% isopropyl alcohol (CA) or 10% Povidone-Iodine (PI) — in an alternating manner. All patients undergoing elective cesarean deliveries during a block will receive the same preoperative skin preparation, in concordance with guidelines for its use. The block assignments will alternate within each year and the order will be reversed after one year to minimize or eliminate seasonal variation in skin infection rates. All patients will receive routine history and physical examination, blood tests, pre-procedure bathing instructions, and preoperative body hair clipping as desired by their primary obstetric provider. Age, body mass index (BMI), gestational age, history of smoking, previous abdominal surgery, number of pregnancies, and live births will be documented before entry into the study. Eligible patients will receive antibiotic prophylaxis with weight-based cefazolin within 60 min before skin incision. We will collect data on preoperative preparation of the surgical site (clipping vs. shaving), type of skin and uterine incision, method of fascia and skin closure, duration of the procedure, use of postoperative antibiotics, and adverse reactions to the skin preparation. The primary endpoint for this study will be any SSI diagnosed within 30 days of cesarean delivery. Our secondary outcomes will be the type of SSI (based on the Center for Disease Control infection classification) and the time to diagnosis of SSI.