The fallopian tubes provide a good microenvironment for egg fertilization and early development of the fertilized egg, while their coordinated peristalsis, cilia oscillation, and tubal fluid flow play an important role in sperm transport, egg uptake, and delivery of the fertilized egg into the uterine cavity; therefore, structurally and functionally normal fallopian tubes are necessary for a normal pregnancy. Many factors may affect the outcome and function of the fallopian tubes, resulting in infertility. Therefore, accurate evaluation of the structure and function of the fallopian tubes is an important part of the diagnosis and treatment of female infertility. Traditional tubal aeration and lavage tests can make a rough judgment of the patency of the fallopian tubes, while X-ray hysterosalpingography can not only clarify the site of tubal obstruction, but also visually show certain lesions in the fallopian tubes and endometrium and the peristaltic condition of the fallopian tubes. Hysteroscopy, on the other hand, can understand the situation in the uterine cavity and has a certain therapeutic effect; laparoscopic tubal passage fluid test is seen as a reliable method to evaluate the patency of the fallopian tubes, but has the disadvantages of being invasive and expensive. 1, tubal aeration test Inject gas (carbon dioxide or oxygen) into the uterine cavity through a catheter, and determine whether the tubes are patent based on the pressure of the injected gas, lower abdominal auscultation, patient’s sensation and the presence of free gas under the diaphragm in abdominal fluoroscopy. Its accuracy is low and there is a potential risk of gas embolism, so it is basically eliminated now. The tubal lavage test is performed by injecting fluid into the uterine cavity through a catheter and determining the patency of the fallopian tubes according to the resistance to fluid injection, the presence or absence of reflux, the amount of fluid injected and the patient’s sensation. It is easy to perform, requires no special equipment, is inexpensive and is widely used. However, there are large errors due to the different tolerance of pain, the size of the uterine cavity and the intensity of response to external stimuli in each individual. In some patients, due to high sensitivity to pain and external stimuli, the placement of the catheter or speculum causes strong contraction of the uterine and tubal smooth muscles, resulting in temporary occlusion of the tubal lumen and or significant reduction of the uterine cavity volume, which eventually leads to a decrease in the amount of fluid injected and an increase in the amount of resistance and reflux fluid, which in turn affects the accuracy of the judgment. At the same time, there are differences in the size of the uterine cavity volume in different patients, which also affects the amount of fluid injected and the results of reflux, which in turn affects the physician’s judgment. 3.X-ray hysterosalpingography (HSG) X-ray hysterosalpingography injects contrast into the uterine cavity and fallopian tubes through a catheter, and X-ray fluoroscopy and radiographs are taken to determine the results according to the contrast developed in the fallopian tubes and pelvis. It can provide information on the size and shape of the cervical canal, uterine cavity and uterine outline. In the absence of proximal tubal obstruction or spasm, it can show the length, diameter, shape and umbilical end folding of the fallopian tubes. Hysterosalpingography can not only clarify whether the fallopian tubes are patent and the site of obstruction, but also make a diagnosis of the internal structure of the fallopian tubes. 4. Hysterosalpingography (HSUG) is performed by injecting special ultrasound diagnostic contrast agents, such as hydrogen peroxide, galactose preparation, carbon dioxide microbubble preparation, etc., through the uterine cavity under ultrasound equipment. In addition, HSUG cannot observe the internal structure of the fallopian tubes and cannot clarify the exact site of tubal obstruction, and it is not easy to obtain satisfactory pictures, so it cannot be widely used at present. 5.Endoscopic examination Laparoscopic examination: inject pigment solution such as melanin into the uterine cavity through the uterine catheter, and observe through the laparoscope that melanin overflows into the pelvic cavity through the umbilical end of the fallopian tube, which means patency. In the case of distal tubal blockage (tubal abdomen and umbilicus), dilatation and thickening of the tubal umbilicus and abdomen and blue staining are seen, but there is no flow of US blue fluid from the tubal umbilicus and into the abdomen. The disadvantage is that it is not possible to know whether the blockage of the interstitial part of the fallopian tube, isthmus and abdomen is true, the location and nature of the blockage, and the mucosal condition of the fallopian tube, so it is only suitable for laparoscopic examination and treatment when the blockage of the umbilical end of the fallopian tube is diagnosed as fluid accumulation or when peri-fallopian tube adhesions are considered. In addition, laparoscopy allows direct visualization of the peri-fallopian tube adhesions, their location, degree of adhesions and the anatomical relationship between the umbilical end of the tubes and the ovaries, and allows simultaneous separation and treatment of the adhesions. Since the test requires general anesthesia or epidural anesthesia, it avoids temporary occlusion caused by pain and other cervical stimulation of the uterine tube smooth muscle spasm and greatly reduces the occurrence of false positives, which is currently the “gold standard” for evaluating the patency of the fallopian tubes. The disadvantages are high technical requirements, greater patient pain, more and heavier possible complications, and higher costs. The above four methods are often used, with tubal lavage being the most commonly used but the misdiagnosis rate is too high and is gradually being eliminated.