OBJECTIVE: Our purpose was to retrospectively review the intraoperative and long-term outcomes of 568 patients with abnormal uterine bleeding who were treated by endometrial ablation over an 11-year period. STUDY DESIGN: From 1983 to 1994, 401 endometrial ablations were performed with the neodymium - yttrium-aluminum-garnet laser and another 167 patients were treated by electrosurgery. The majority of the patients were treated for irregular, heavy menses. Fifty-seven had ablation because of abnormal bleeding associated with a serious medical disorder, 12 with a bleeding diathesis, and 50 with morbid obesity. All patients had preoperative endometrial sampling that demonstrated benign histology. Nineteen patients had submucous myomas that were resected at the time of hysteroscopic ablation. All patients received preoperative and postoperative suppression. The minimum follow-up period was 1 year. RESULTS: The average operative time was 32.5 minutes. The mean hospital stay was 8 hours. Four patients who received 32% dextran 70 in dextrose (Hyskon) as the distending medium had pulmonary edema postoperatively. One case of endometritis was also detected. No uterine perforations were observed. Amenorrhea developed in 58% of the patients, 34% reported light or normal menstrual flow, and 8% did not respond (continued heavy flow). CONCLUSION: This study represents one of the largest published series of endometrial ablation, with a mean follow-up of 4.5 years. It demonstrates that hysteroscopic endometrial ablation is a reliable, safe alternative to hysterectomy for the surgical management of abnormal uterine bleeding. (AM J OBSTET GYNECOL 1996;174:908-13.)