LARRY C. GILSTRAP, III, MD, Emma Sue Hightower Professor and Chair, Department of Obstetrics, Gynecology, and Reproductive Sciences, The University of Texas-Houston Medical School, Chief of Obstetrics and Gynecology Service, Memorial Hermann Hospital, Memorial Hermann Healthcare System, Houston, Texas F. GARY CUNNINGHAM, MD, JA Pritchard Professor, Chair, Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center at Dallas, Chief of Obstetrics and Gynecology, Parkland Memorial Hospital, Dallas, Texas J. PETER VANDORSTEN, MD, Professor and Chair, Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina Less