 The Prophylactic Negative Pressure Wound Therapy in Obese Women at Cesarean Trial is a large pragmatic multi-center randomized clinical trial designed to evaluate the effectiveness, safety and cost-effectiveness of prophylactic negative pressure wound therapy NPWT - a closed, sealed system that applies negative pressure to the wound surface via a single-use, battery-powered, portable device - to decrease surgical site infections SSIs in obese women. 