Endometriosis lesions were first observed using a microscope by Karlvon Rokitansky in 1860, and the symptoms of this condition were described in medical textbooks thousands of years ago. Endometriosis is an inflammatory, estrogen-dependent disease associated with pelvic pain and infertility. The disease affects approximately 10% of women of childbearing age and 20%-50% of infertile women. Ectopic lesions are primarily located in the pelvic peritoneum and ovaries, and rarely in the heart, pleura, lungs and brain. Despite the high incidence of endometriosis and its serious impact on quality of life, the pathogenesis of the disease has not been fully elucidated. The causes are as follows: 1. Implantation theory The menstrual blood flows backwards and the endometrium is implanted. During menstruation, menstrual blood is discharged from the uterus and vagina in a downward flow, but a small portion of the menstrual blood or the shedding endometrial fragments for other reasons flow into the abdominal cavity from the fallopian tube and are planted in the surface layer of the pelvic organs to form endometriosis lesions. 2. Chemogenic endometrium Plasma membrane epithelium, chemogenic endometrium. In human body during embryonic development, ovarian surface epithelium, peritoneum, vaginal rectal diaphragm and umbilicus are all derived from somatic epithelium. These tissues are able to transform under the stimulation of gonadal hormones, inflammation and mechanical factors to form another kind of tissue, which can likewise be metastasized into endometrium. 3. Benign metastasis Blood and lymphatic benign metastasis. This is a relatively rare cause of morbidity. It occurs in the lungs, meninges, pericardium, extremities and other distal endometriosis, and develops by transferring endometrial debris to rest on an organ or tissue through the blood circulation or lymphatic system. 4.Medical endometrial transplantation This is an artificially caused transplantation of endometrium to certain parts of the uterus, mostly seen during cesarean section, early and mid-term pregnancy scraping, perineal lateralization during delivery, abortion, etc. 5. Defective immune defense function The endometrium that flows back to the abdominal cavity with menstrual blood is like a foreign body that activates the immune system in the body, mobilizing a large number of immune cells and body fluids to surround and eliminate it, and if the body’s immune function is defective, it will develop into endometriosis. 6, genetic factors Endometriosis has a certain genetic predisposition and family aggregation, with a family history of the disease in the majority of people suffer from this disease.