Hysteroscopy is a fiberoptic light source endoscope that is used to enter the uterine cavity using the anterior part of the mirror, and is the preferred method of examination for gynecological bleeding disorders and intrauterine lesions. I. Scope of examination: 1. cervical canal: the canal can be observed for polyps, inflammation, exudation and hyperplasia and other lesions and given treatment; 2. inside the uterine cavity: the uterine cavity is observed and evaluated for normal morphology, abnormal endometrial performance, such as whether the thickness of the endometrium is normal, whether there are abnormalities such as polyps and myomas, and whether there are adhesions. There is also whether the opening of the fallopian tubes is normal, whether there are longitudinal septa and adhesions in the uterine cavity, and whether there are polyps and fibroids in the endometrium of the uterine cavity. Applicable diseases: 1. abnormal uterine bleeding; 2. intrauterine occupying diseases, such as uterine polyps and submucosal myomas; 3. abnormal intrauterine devices and foreign bodies; 4. repeated pregnancy failure or infertility; 5. uterine adhesions; 6. uterine malformations; 7. abnormal uterine cavity imaging; 8. female vaginal foreign bodies or drainage; 9. post-operative hysteroscopy follow-up. It is recommended to avoid sexual intercourse after hysteroscopy and to pay attention to keep the vagina clean and hygienic to avoid infection. In addition, hysteroscopy is not recommended for patients with reproductive tract or pelvic inflammatory disease to avoid spreading the infection.