The diagnosis and treatment of irregular menstruation requires an ultrasound examination. The main causes of irregular menstruation are endocrine disorders or uterine pathology, and the examination should include the thickness of the endometrium and the morphology of the uterus. In endocrine disorders, the endometrium as the target organ of the whole gonadal axis will be affected, such as endometrial hyperplasia, which will lead to scanty menstruation and delayed menstruation. If the thickness of the endometrium is too large, there will be heavy menstrual flow, prolonged menstrual period and shortened cycle, etc. Ultrasonography can determine whether the thickness of the endometrium is normal or not, and it should be coupled with female hormone examination in addition to ultrasonography. If the uterus has multiple fibroids, adenomyosis, endometrial polyps, etc., which can also cause menstrual disorders, ultrasound can directly determine the size of the uterine body, the number of fibroids, the uterine cavity whether there are abnormal echoes and abnormal blood flow signals, which can be used to suggest the direction of further diagnosis and treatment.