Fallopian tube factors are an important factor in female infertility, accounting for about 40% of infertility. So, what tests are available to help us know if the fallopian tubes are open? There are many tests for tubal patency, such as tubal lavage, hysterosalpingography under X-ray, uterine tubal ultrasound, laparoscopy and abdominal exploration. Among them, X-ray hysterosalpingography with iodine oil and laparoscopy are highly accurate and are reliable means to confirm the diagnosis of tubal obstruction. The following is an explanation of the most common methods. 1.Hysterosalpingography: Iodine is injected into the uterine cavity through the son. The iodine can circulate through the uterine horns to the bilateral fallopian tubes, and because the iodine is a high specific gravity substance, it can form a clear contrast with the surrounding tissues under X-ray radiography, and the location where the iodine arrives can be judged by the developing situation to understand the situation of the uterus and the fallopian tube lumen. Advantages: simple operation, generally no anesthesia is required, non-invasive and less expensive than laparoscopy. Disadvantages: imaging, occasionally unsatisfactory contrast and false positive may be seen; cannot be performed in iodine allergic patients; requires X-ray radiographs and has potential effects of X-ray exposure. 2.Under ultrasound tubal imaging: With the development and progress of ultrasound instruments, 4D under ultrasound imaging technology has been developed in recent years. Through the sub-injection of microsphere injection into the uterine cavity, an image different from the echo of surrounding tissues can be produced under ultrasound, forming an obvious contrast with the surrounding tissues, and the uterus and fallopian tube lumen can be imaged through a series of ultrasound imaging techniques. Advantages: simple to perform, no X-ray is required, and better protection for patients and medical staff. Disadvantages: skilled ultrasound operators are needed and there are very few false positives. 3, tubal lavage: by injecting melanin or saline into the uterine cavity from the cervix and then flowing into the fallopian tubes from the uterine cavity, the operating doctor will judge whether the fallopian tubes are open or not mainly according to the size of the resistance when pushing the fluid and the situation of fluid reflux. The accuracy of this method is poor and it has been gradually replaced by other examination methods. 4.Laparoscopy: Laparoscopy can visually observe the condition of the fallopian tubes, including the surrounding adhesions, the site and degree of adhesions, and the anatomical relationship between the umbilical ends of the fallopian tubes and the ovaries. Laparoscopy needs to be performed under general anesthesia and there are anesthetic risks; it is not suitable for cases such as pelvic masses and reproductive system malformations; it is more expensive; it is not the preferred method of examination.