&Nbsp. . Classification of uterine lesions: 1. Congenital uterine dysplasia: The human uterus is an organ formed by the development and transformation of the accessory mesephritic duct. Bilateral luminal insufficiency, or non-absorption or incomplete absorption of the mediastinum after fusion can cause uterine malformations. Different degrees of mediastinal uterus is the most common deformity, which can easily lead to early miscarriage. Others include single-horned uterus, double-horned uterus and twin uterus, which can cause abnormal implantation of pregnant eggs, affect the development of placenta and fetus, and cause miscarriage. 2. Uterine adhesions: multiple artificial abortions, excessive curettage, uterine cavity surgery and retention of pregnancy materials can cause intrauterine adhesions. About 14% of patients with intrauterine adhesions have miscarriages. Adhesion causes shrinkage and deformation of the official cavity, reduction in the area of the endometrium, and damage to the functional layer of the endometrium, which can affect embryo implantation and development and lead to abortion. 3. Uterine fibroids: The relationship between uterine fibroids and miscarriage depends on the type, location, size, and secondary changes of the fibroids. Submucosal fibroids deform the uterine cavity, and shallow ulcers are often formed on the surface of the intima, which affects the implantation and development of pregnant eggs. The obstructive effect of fibroids makes the intima and muscle blood vessels dilate, hyperemia, and reduce blood flow, which is not conducive to embryonic development. In addition, the local compression of fibroids causes deformation and degeneration of the uterine cavity, causing uterine contraction and miscarriage. 4. Cervical insufficiency: The main manifestations of cervical insufficiency are premature delivery and middle and late repetitive abortions. The incidence of recurrent abortions is 8% to 15%. (1) Congenital cervical insufficiency: Approximately 1/3 of patients with cervical insufficiency are caused by congenital factors, often accompanied by abnormal Müllerian duct development, such as unicornuate uterus or mediastinal uterus, or cervical histological defects. Insufficient cervical elastin content. (2) Acquired cervical insufficiency: It often occurs after obstetric or gynecological surgery injuries, such as rough dilation of the uterine orifice during abortion, cervical conization, and when the cervical laceration is not sutured in time during delivery. It can also be secondary After the anatomical structure of the cervix or lower part of the uterus changes, such as fibroids. (3) Physiological cervical insufficiency: Some scholars believe that the internal cervical sphincter functions as a functional sphincter during pregnancy, and patients with subclinical uterine contractions or hypotonic internal cervical sphincter weaken the function of the internal cervical sphincter. In addition, bromelain and papain can relax the cervix. Cervical insufficiency, unable to withstand the increase in intrauterine pressure as the month of pregnancy increases, and abortion due to spontaneous rupture of the amniotic membrane often occurs in the second trimester, which can discharge completely normal embryonic tissue.