1. Darnell Army Community Hospital, Ft. Hood, Texas; Rockford Memorial Hospital, Rockford, Illinois; Madigan Army Medical Center, Tacoma, Washington; Department of Epidemiology, Columbia University School of Public Health, New York, New York
2. Darnell Army Community Hospital, Ft. Hood, Texas; Rockford Memorial Hospital, Rockford, Illinois; Madigan Army Medical Center, Tacoma, Washington; Department of Epidemiology, Columbia University School of Public Health, New York, New York; Department of Obstetrics and Gynecology, Madigan Army Medical Center, Tacoma, WA 98431