Tubal obstruction is an important cause of female infertility, accounting for about 30% to 50% of female infertility as reported in the literature, and its incidence is increasing with the increase in the number of abortions. The tissue structure of the female reproductive system and the process of conception The tissue structure of the female reproductive system includes the uterus, the fallopian tubes and the ovaries, of which the fallopian tubes are divided from the inner (uterine end) to the outer (ovarian end) into the interstitial part, the isthmus, the abdomen and the funnel (umbilical end). The fallopian tubes “catch” the oocytes discharged from the ovaries and enter the fallopian tubes, where they rendezvous with the sperm entering the fallopian tubes via the vagina and the uterus to form a fertilized egg, which moves toward the uterine cavity, lays in the endometrium, and gradually develops into an embryo, which then forms a fetus. When the fallopian tube is obstructed for various reasons, the channel of conception is blocked and therefore the natural conception process cannot be completed. Diagnosis of tubal obstruction 1. Tubal lavage: saline or antibiotics are pushed into the uterine cavity under pressure. The normal uterine cavity volume is 5~7ml, and the general lavage does not exceed 10~20ml. Those with lower abdominal pain are considered as tubal obstruction. Compared with hysterosalpingography, the advantage is that it is easy to operate and there is no radiation exposure. The disadvantage is that the site of obstruction and the situation in the uterine cavity cannot be clarified. 2.Hysterosalpingography: Under the X-ray machine, the uterus and fallopian tubes are observed by contrast injection, fluoroscopy and radiography. The test is an intuitive image display, which can observe: the situation in the uterine cavity, including whether there are abnormalities in the development of the uterus, whether there are polyps and other occupying lesions, etc.; the condition of the fallopian tubes: whether they are patent, waterlogged, tubal lesions such as tuberculosis, endometriosis, etc.; the condition of the peripelvic area of the fallopian tubes near the pelvic cavity ( peritoneal cavity): such as peripelvic adhesions, intrapelvic adhesions, etc. The latter are incompletely displayed (covered with contrast to be displayed) and have low accuracy compared with laparoscopy. Treatment of tubal obstruction: Intervention to unblock the obstructed fallopian tubes is a proven treatment for this disease. 1. Time of surgery: 3-7 days after menstruation. 2.Procedure method: Similar to hysterosalpingography, a coaxial catheter is used for intra-uterine recanalization to select and enter the fallopian tubes with a micro-catheter and flush the tubes with a guide wire or with contrast agent under pressure. After confirming that the fallopian tubes are open by contrast, a therapeutic fluid is pushed in. No anesthesia is needed during the procedure, which takes about 30 minutes. 3.Post-operative treatment: The treatment will be handled by a specialized infertility physician, including physiotherapy and water lavage. Issues to be emphasized: 1. Diagnosis of tubal obstruction: Tubal imaging is an important means of diagnosis. There are two types of contrast agents used – aqueous (iodine water) and oil (iodized oil), and at present, most of them are used in China. Iodine water, because of its low surface tension and good fluidity, can reflect the fluidity of the fallopian tubes, but not well. Iodized oil, because of its high surface tension and poor fluidity, can reflect the fluidity of the fallopian tubes. From our experience, iodine water imaging of patent fallopian tubes may not necessarily lead to conception, while iodized oil imaging of patent fallopian tubes can meet the requirements for conception. 2. Interventional surgery: Gentle and gentle operation is required to minimize tubal damage. Repeated operations can cause damage to the opening of the fallopian tubes and even cause medical re-obstruction; it is recommended to use super-slip guidewire to unblock the fallopian tubes; although the catheter guidewire is very soft, it has a certain degree of hardness after all, and we use liquid pressure to recanalize the fallopian tubes to reduce the damage to the fallopian tubes. After more than one thousand cases, we have confirmed that the success rate of the operation is about 90% (i.e. no need to use the guidewire to recanalize) and the conception rate is obviously increased. 3. About post-operative treatment: The treatment of tubal obstruction should take conception as the ultimate goal, i.e. all diagnosis and treatment should be set around the ultimate goal of conception. The treatment of tubal obstruction should be planned as a whole, including preoperative diagnosis, interventional surgery (to minimize tubal damage), postoperative treatment and selection of the time of conception, etc. Interventional unblocking of the fallopian tubes is only one of the treatment stages, and postoperative treatment is equally important as interventional surgery. 4. Problems with combined hysteroscopy and laparoscopy: hysteroscopy is to solve the problems in the uterine cavity, such as polyps and adhesions in the uterine cavity, while laparoscopy is to solve the problems in the umbilical end of the fallopian tube and its surrounding peritoneal cavity (pelvis), which cannot enter the fallopian tube because of its thicker diameter, therefore, tubal obstruction is not a good indication for combined hysteroscopy. Therefore, tubal obstruction is not a good indication for combined laparoscopic surgery. Some hospitals use hysteroscopic tubal intubation to treat tubal obstruction, because it is impossible to observe whether the tubes are reopened after the instruments enter the tubes, and some patients even have tubal perforation as if the tubes have been reopened, so we do not recommend this surgical method to unblock the tubes.