Menorrhagia is one of the most common reasons for referral to gynecologists. Many women do not respond to medical treatment and are candidate for hysterectomy. Some of them who are in their middle age don’t like to have hysterectomy and those who are older are not candidate for medical treatment and surgical hysterectomy due to internal diseases in this age. So, endometrial ablation is one of suggested treatments. This clinical trial will be done on women with menorrhagia who have not responded to medical treatment. Patients are categorized into two groups: endometrial ablation with thermal balloon (intervention group, 35 patients) and endometrial ablation with hysteroscopy (control group, 25 patients). Information such as age, parity, BMI, dysmenorrhea, menstrual period, duration of menorrhagia, treatment taken, medical history, underlying disease, history of previous surgery will be recorded. Postoperative complications of hysteroscopy including bleeding, infection, uterine perforation, thermal injury, and complications after thermal balloon including thermal injury to the bowel, bleeding, uterine perforation, adenexal necrosis are recorded. All patients are followed for one year. Outcomes for each patient will be recorded for 6 months and 12 months after treatment.