Intrauterine lesions are a common cause of infertility, accounting for 10-20% of female infertility. Diagnosis of intrauterine lesions mainly relies on abdominal or vaginal ultrasonography, diagnostic curettage and hysteroscopy. Vaginal ultrasonography is the preferred method of examination, and a common intrauterine abnormality on ultrasound is the discovery of an unevenly echogenic or heterogeneous hypoechoic endometrium during the menstrual augmentation phase. In some cases where a hyperechoic mass is found in the uterus and endometrial or uterine cavity abnormalities are suspected, the most common method used for definitive diagnosis or treatment is diagnostic curettage. Diagnostic curettage is an invasive diagnostic and therapeutic procedure that may carry the risk of infection and uterine adhesions, whereas many patients in whom ultrasound suggests an abnormality are normal on hysteroscopy. Therefore, diagnostic curettage by ultrasound alone can increase unnecessary trauma in many patients with normal uterine cavities. Possible hysteroscopy and endometrial tissue biopsy is the gold standard of modern diagnosis of intrauterine lesions, but the test requires high requirements for doctors, equipment and venues, due to the need for dilatation of the uterus, which causes a high degree of pain, and there may be perforation of the uterus, water intoxication and other serious complications, so it restricts the wide application of the clinic. Hysteroscopy does not allow for simultaneous visualization of the uterine cavity beyond the uterine cavity and has limitations in determining the relationship of intrauterine lesions to the myometrium. Intrauterine sonography (SHG) is a uterine examination technique developed in recent years, which is a new examination method based on diagnostic ultrasonography. It is performed by injecting saline into the uterine cavity to make the uterine cavity expand, and the uterine cavity displays a liquid dark area, which creates a good window of translucency and a contrast area, separates the endometrium, and facilitates the display of the surface of the endometrium, thus improving the ultrasound’s display of intrauterine abnormality and its relationship with the myometrium, and improving the display of intrauterine abnormality and its relationship with the myometrium. This improves the sensitivity and specificity of ultrasound in the diagnosis of intrauterine lesions, thus improving the relationship of ultrasound to intrauterine abnormalities and their relationship with the myometrium, and the ability to distinguish endometrial and myogenic lesions, and improving the sensitivity and specificity of ultrasound in the diagnosis of intrauterine lesions; some studies have concluded that the diagnosis of the presence of endometrial abnormalities in infertile women can be compared with that of hysteroscopy, and the operation of SHG is easy, and it does not need to dilate the uterus, and it only needs to be put into the 5-F pediatric gastrostomy tube, push in 5-20ml of saline, and then the uterus can be clearly visualized under the B-scan. Under ultrasound, the uterine cavity can be clearly observed and the relationship between intrauterine lesions and the muscular layer can be shown, which is less painful, non-invasive and without serious complications. The cost of transvaginal ultrasound and SHG is less than one third of hysteroscopy. Therefore, for patients with intrauterine abnormalities detected by ultrasound, SHG can be the first choice of intrauterine examination, and the examination can be carried out during ultrasound, avoiding the trouble of repeated visits to the doctor, and then carry out diagnostic scraping or further hysteroscopy for confirmed abnormalities, avoiding unnecessary trauma and pain to the patients. For patients with abnormalities, after treatment, the examination can be performed one week later to understand the effect of treatment, which has the advantage of repeated examination. It is the first choice for diagnosis of uterine cavity lesions in our department. For women with regular menstrual cycle, this examination is usually done within 3~7 days after the end of menstruation.