Hysteroscopy is the modern gold standard for the diagnosis of uterine cavity lesions; hysteroscopic surgery makes it possible to eradicate diseases that used to be treated by removing the uterus, and to preserve the reproductive function of the uterus for those who have fertility requirements. The main advantages are less trauma, less bleeding, faster recovery, shorter hospital stay, lower cost, no incision in the abdomen, and preservation of the integrity of the female organism. Indications for hysteroscopy: 1. abnormal uterine bleeding; 2. occupying lesions in the uterine cavity (such as fibroids and endometrial polyps); 3. examination of the uterus and fallopian tubes for infertility; 4. examination of uterine and cervical factors for recurrent miscarriage and premature delivery; 5. evaluation of abnormal uterine image changes (such as ultrasound and hysterosalpingography); 6. positioning and removal of lost, broken and embedded intrauterine devices; 7. 7.Incomplete abortion resulting in embryonic tissue and intrauterine foreign body residue; 8.Confirmation and differential diagnosis of uterine malformation; 9.Early diagnosis of endometrial cancer. Indications for hysteroscopic treatment: 1. endometrial electrosurgery can be performed via hysteroscopy for functional bleeding and increased menstrual flow that have not been treated for a long time; 2. endometrial polyps can be removed; 3. submucosal fibroids and myomas that protrude between the muscle walls into the uterine cavity can be removed from the uterine cavity via hysteroscopy; 4. uterine malformations (such as uterine septum) that cause infertility and recurrent miscarriage can be corrected via hysteroscopic electrosurgery; 5. 6. difficult removal of intrauterine device due to disorientation, rupture, and embedment; 7. incomplete abortion resulting in embryonic tissue residue, fetal bone residue, etc.; 8. proximal tubal obstruction, tubal sterilization; 9. excision of cervical inflammatory lesions.