To estimate the frequency, indications, and complications of cesarean hysterectomy. This was a prospective, 2-year observational study at 13 academic medical centers conducted between January 1, 1999, and December 31, 2000, on all women who underwent a hysterectomy at the time of cesarean delivery. Data were abstracted from the medical record by study nurses. The outcomes included procedure frequency, indications, and complications. A total of 186 cesarean hysterectomies (0.5%) were performed from a cohort of 39,244 women who underwent cesarean delivery. The leading indications for hysterectomy were placenta accreta (38%) and uterine atony (34%). Of the hysterectomy cases with a diagnosis recorded as accreta, 18% accompanied a primary cesarean delivery, and 82% had a prior procedure (P<.001). Of the hysterectomy cases with atony recorded as a diagnosis, 59% complicated primary cesarean delivery, whereas 41% had a prior cesarean (P<.001). Major maternal complications of cesarean hysterectomy included transfusion of red blood cells (84%) and other blood products (34%), fever (11%), subsequent laparotomy (4%), ureteral injury (3%), and death (1.6%). Accreta hysterectomy cases were more likely than atony hysterectomy cases to require ureteral stents (14% compared with 3%, P=.03) and to instill sterile milk into the bladder (23% compared with 8%, P=.02). The rate of cesarean hysterectomy has declined modestly in the past decade. Despite the use of effective therapies and procedures to control hemorrhage at cesarean delivery, a small proportion of women continue to require hysterectomy to control hemorrhage from both uterine atony and placenta accreta. II. © 2009 Lippincott Williams & Wilkins, Inc.