I. Pathogenesis of endo-infertility 1. Abnormalities in pelvic anatomy and tubal structure or function Patients with moderate or severe endo-infertility can often detect endo-adhesions or ovarian cysts resulting in tubal distortion or obstruction. If the peripheral lesions are severe they may also lead to atresia of the tubal umbilicus. The severity of clinical symptoms can be disproportionate to the extent of the lesion, and many patients with mild endometriosis are combined with infertility, so other factors affecting conception exist in patients with endometriosis. Many pathogenic mechanisms and factors influencing low fertility associated with endometriosis have been proposed. Abnormalities in all parts of the reproductive process in women have been suggested as possible causes of endoheterosis-related low fertility. The effect of endohetero on folliculogenesis Endohetero may be associated with various ovarian abnormalities, such as abnormal follicular development, anovulation, hyperprolactinemia, luteal insufficiency, and luteinized late ruptured follicle syndrome (LUFS). 3, the effect of endoallograft on fertilization 4, the effect of endoallograft immune inflammatory response Cytokines in ascites, especially interleukins, are thought to have a possible hindering effect on fertilization, oocyte division and other reproductive processes. The relationship between peritoneal fluid and infertility. Prostaglandins (PG) are mediators of oocyte discharge from the preovulatory follicle. elevated PG levels interfere with the timing of oocyte release from the preovulatory follicle or may somehow desensitize the follicle and interfere with oocyte release. Elevated PG can affect tubal motility and egg transport, which can lead to increased tubal peristalsis and abnormal nodal rate, affecting the operation of the pregnant egg, resulting in asynchronous development of the pregnant egg and metaphase changes in the endometrium of the uterine cavity, and affecting the implantation of the pregnant egg. 5. The effect of endometriosis on implantation Many studies suggest that embryo implantation is impaired in patients with endometriosis, which may be related to the defects of the uterus itself, the abdominal fluid or the decreased quality of the embryo itself. It has been suggested that abnormal contractions of the uterus in patients with endometriosis affect sperm transport and embryo implantation, reducing fertility. The reduced fertility may be due to impaired oocyte and embryo quality. Endometriosis may cause infertility for a variety of reasons. Impaired folliculogenesis, especially in moderate to severe endometriosis, and low quality oocytes can impair fertilization and implantation rates. Inflammatory follicular fluid and peritoneal fluid can also cause defects in fertilization and implantation. Diagnosis and treatment of endometriosis-related infertility Laparoscopy is often used as the “gold standard” for the diagnosis of endometriosis. Treatment of endometriosis-related infertility (1) Laparoscopic surgery: Laparoscopic surgery is the first choice for mild or moderate to severe endometriosis. During surgery, electrocautery is performed as much as possible on the lesion to free the ovary and break down the adhesions. Laparoscopic surgery is as effective as open surgery regardless of the presence of ectopic cysts. There are different treatments for ovarian endometriotic cysts, such as cyst excision, puncture and drainage, and laser vaporization, depending on the surgeon’s skill and laparoscopic equipment. Pregnancy varies among the various approaches, but there is no positive literature on which approach is more effective. Repeated procedures and excessive electrocoagulation for hemostasis, especially in the hilar region, are not advocated and are associated with interstitial ovarian damage. Because repeated surgery can result in loss of most of the ovarian cortex, is a reduced response to IVF superovulation, and even causes premature ovarian failure, suture hemostasis is recommended for ovarian surgery. The improvement of endometrial infertility by surgery depends not only on the condition of the fallopian tubes themselves but also on the surgical technique of the surgeon. A surgeon who has a better understanding of the processes of fertilization and implantation is better able to improve the pregnancy rate of infertile patients through surgery and postoperative adjuvant therapy. Medication can reduce the symptoms of endometriosis in 80 to 90 percent of women. Therefore, pharmacological treatment is widely used in women with endometriosis-related infertility. (2) Assisted reproductive techniques for endo-infertility: Intrauterine insemination has been frequently used in patients with mild endo-infertility. In vitro fertilization-embryo transfer technique and its derivatives such as single sperm oocyte injection can overcome pelvic anatomical abnormalities and obtain high clinical pregnancy rates. pre-IVF GNRHA application: Many studies have concluded that endometriosis can reduce pregnancy rates in IVF and that pre-IVF cycle GNRHA treatment can improve pregnancy outcomes. In IVF-ET GNRHA is mainly used to suppress the LH peak, to produce a FLARE UP effect in low response and to synchronize the cycles of the egg donor and the egg recipient. The commonly used protocol in China is: GNRHA 3.75MG/28D,2–3 doses followed by exogenous gonadotropin stimulation of follicle growth at 30–40D after the last GNRHA injection. The advantage is that it can be used for the last time of endo-heterozygosity control to assist the pregnancy. In severe endometriosis, postoperative GNRHA treatment can improve the chances of conception because surgery does not completely remove the lesion and minimally invasive surgery does not completely block the intraoperative dissemination of endometrial tissue and endometriosis can be treated surgically. In conclusion, laparoscopy is the first choice in the examination of endometriosis combined with infertility, pelvic dissection to evaluate the patency of the fallopian tubes, and again to detect the lesion and perform electrocautery treatment. Pharmacological treatment does not improve the postoperative pregnancy rate. Repeat surgery of the ovaries is not advocated, and age must be taken into account in the examination and treatment to achieve individualized treatment.