To determine the feasibility and potential efficacy of thermal balloon ablation of the endometrium in the outpatient setting without the need for general anesthesia or conscious sedation. Prospective observational study. Outpatient hysteroscopy clinic in a universityaffiliated teaching hospital. Fiftythree consecutively recruited women with menorrhagia that was unresponsive to medical treatment. Thermal balloon endometrial ablation using local anesthetic without conscious sedation. Procedure feasibility, change in menstrual symptoms, and patient satisfaction and quality of life (Menorrhagia Utility Scale and EuroQol) at 6-month followup. Thermal balloon ablation was successfully completed in 50 (94%) of 53 women. The three failed procedures consisted of one case in which the woman could not tolerate the procedure because of severe discomfort, one case of equipment failure, and one case in which the balloon catheter could not be inserted into the uterine cavity. Completed outcome questionnaires were returned by 49 (98%) of 50 treated women. Improvement in menstrual loss was experienced by 39 (80%) of 49 women, and satisfaction with the outcome of treatment on menstrual symptoms was reported by 33 (67%) of 49 women. Significantly higher conditionspecific qualityoflife scores were associated with treatment satisfaction. Thermal balloon ablation of the endometrium is feasible in the outpatient setting. Improvement in menstrual symptoms and satisfaction with the outcome of treatment appear to be comparable to published inpatient data. Further studies are required to determine the costeffectiveness of outpatient compared with inpatient thermal balloon therapy. To determine the feasibility and potential efficacy of thermal balloon ablation of the endometrium in the outpatient setting without the need for general anesthesia or conscious sedation. Prospective observational study. Outpatient hysteroscopy clinic in a university affiliated teaching hospital. Fiftythree consecutively recruited women with menorrhagia that was unresponsive to medical treatment. Procedure feasibility, change in menstrual symptoms, and patient satisfaction and quality of life (Menorrhagia Utility Scale and EuroQol) at 6-month follow-up. Thermal The three failed in one of the cases the woman could not tolerate the procedure because of severe discomfort, one case of equipment failure, and one case in which the balloon catheter could not be inserted into the uterine cavity. Completed outco mementires were returned by 49 (98%) of 50 treated women. Improvement in menstrual loss was experienced by 39 (80%) of 49 women, and satisfaction with the outcome of treatment on menstrual symptoms was reported by 33 (67%) of 49 women. Significantly higher conditionspecific qualityoflife scores were associated with treatment satisfaction. Thermal balloon ablation of the endometrium is feasible in the outpatient setting. Improvement in menstrual symptoms and satisfaction with the outcome of treatment appear to be comparable to published inpatient data. Further studies are required to determine the costeffectiveness of outpatient compared with inpatient thermal balloon therapy.