Uterine adhesions are a common gynecological condition and can lead to a series of complications such as abnormal menstruation, infertility and habitual miscarriage. Any factors that cause endometrial destruction can cause cavity adhesions, so how to avoid the occurrence of cavity adhesions and how to treat them once they occur? I. History of understanding of uterine adhesions Uterine adhesions (IUA) were first reported in 1894 and further described by Joseph Asherman, an Israeli gynecologist, in 1948, hence the name Asherman syndrome, which is closely related to basal lamina damage and infection caused by uterine operations: 1. Uterine operations include uterine operations during pregnancy: abortion, medication 1. Uterine operations include those performed during pregnancy: abortion, abortion with drugs, midterm induction of labor, postpartum curettage, and gravidity clearance. 2. Non-pregnancy uterine operations: diagnostic curettage, hysteroscopic myomectomy, endometrial polyp electrosurgery, etc. How to treat cavity adhesions Recurrent miscarriage, infertility and chronic pelvic pain caused by cavity adhesions can be observed without treatment in patients without clinical symptoms and without fertility requirements. The necessity of surgery is controversial in patients with scanty menses but no fertility requirements. This shows that there are indications for the treatment of uterine adhesions, such as pain, abnormal menstruation (including blood in the uterine cavity) or fertility-related problems, which require hysteroscopic surgery. In patients with infertility, recurrent miscarriages, and especially in those who have excluded other factors causing fertility problems, hysteroscopy can be performed to clarify the diagnosis. Treatment principles: 1) comprehensive separation of adhesions to restore the normal size and shape of the uterine cavity; 2) restoration of anatomical structures, exposure of both uterine horns and the fallopian tubes, and reduction of damage to residual endometrium, in which extensive uterine adhesions may be difficult to separate completely in a single operation and require multiple operations; 3) postoperative adjuvant therapy to promote endometrial repair and restore menstruation and reproductive function; 4) prevention of adhesions. Adhering to the above principles it is not difficult to restore the uterus to normal or approximately normal uterine anatomy under hysteroscopy, to further restore menstruation, to prevent re-adhesion, to promote endometrial repair and proliferation and to improve pregnancy rate. The diagnosis and treatment of severe uterine adhesions The main examination modalities for severe uterine adhesions are ultrasound and hysteroscopy, and studies have shown that the diagnostic compliance rate between HSG and hysteroscopy is 91,0% and the misdiagnosis rate is 9,0% by uterine cavity examination. The diagnostic criteria were 9-12 according to the American AFS score (extent of adhesions, type of adhesions, menstrual status) and according to the ESGE classification method (relationship to the uterine horns and tubal openings): grade IV and V, specifically fibrous cord adhesions causing partial atresia of the uterine cavity and both uterine horns; extensive adhesions scarring amenorrhea or significantly reduced. Treatment is divided into surgical treatment and postoperative adjuvant treatment. The main objective of the latter is to prevent recurrence of postoperative adhesions by: 1. physical barriers: postoperative placement of a water-filled balloon, postoperative placement of an intrauterine device, intrauterine placement of drugs such as hyaluronic acid, and anti-adhesive effects based on the amniotic membrane. 2. Pharmacological treatment: estrogen, drugs to improve blood circulation such as vasodilators, treatment of mycoplasma infection, etc., herbal treatment. Stem cell transplantation is a hot spot for future research. 3. Postoperative treatment: antibiotics to prevent infection, intrauterine injection of 3-5 cc of cross-linked hyaluronic acid (HA) gel or intrauterine placement of a balloon, removal and placement of a metal ring in 3-5 days, estrogen cycle therapy, and hysteroscopic second exploration again after 1-2 menstrual cycles. Fourth, severe uterine adhesions still face challenges Hysteroscopic electrosurgery can achieve the restoration of uterine cavity morphology, balloon, IUD, hormone, sodium hyaluronate, amniotic membrane and other parts to prevent re-adhesion, but the prognosis of restoring menstruation and improving pregnancy rate are still difficult to achieve the challenge, the study of endometrial regeneration becomes the key and will certainly become an important topic of future research.