In general, hysteroscopy is feasible for any form of intrauterine lesion or for those who need to make an accurate diagnosis and surgery of the lesion. 1, Abnormal uterine bleeding in fertile, perimenopausal and postmenopausal patients. 2. For any patient with suspected abnormal sonography in the uterine cavity. 3.For patients associated with infertility and sterility. 4.Patients who need long-term oral triamcinolone or HRT treatment after surgery for breast cancer, etc. 5.For patients with secondary dysmenorrhea. 6.Patients with abnormal cytology of uterine cavity aspiration or further pathological diagnosis of endometrium. 7.For re-evaluation of uterine cavity after preforming complex uterine surgery. 8, Classification of uterine fibroids or for patients with multiple fibroids to clarify the presence of submucosal fibroids. 9.Hysteroscopy for patients who have difficulty in lowering the ring to check whether there is ectopic or embedded ring. 10.Staging of endometrial cancer and abnormal vaginal fluid discharge.