If the ultrasound suggests that an endometrium of 16mm is abnormal. For women with a history of sexual intercourse, the first step is to clearly diagnose pregnancy. If the blood chorionic gonadotropin value is normal, pregnancy can be ruled out, but endometrial pathology can not be ruled out, it is recommended to do a hysteroscopic exploration, in the hysteroscopy to understand the condition of the endometrium, there is no abnormal foci, such as endometrial polyps and so on. Under the hysteroscope, endometrial lesions are excised or endometrial scraping is performed, and pathologic examination is sent to clarify the diagnosis after the operation. If endometrial polyps, polypoid hyperplasia, endometrial simple hyperplasia, or hyperplasia are identified, it is recommended that progesterone be given to prevent recurrence. If it suggests malignancy, timely surgical treatment should be carried out.