The normal endometrial thickness varies with the menstrual cycle and is not constant. The endometrial thickness of 8mm is normal and should be judged in the context of whether a woman is menopausal or not.1. Before menopause: an endometrial thickness of 8mm is generally normal. Before menopause, the first half of the menstrual cycle is called the follicular phase, when the endometrial thickness is usually bounded by 10mm, less than 10mm is normal. In the second half of the luteal phase of the menstrual cycle, the thickness of the endometrium is usually defined as about 20mm, and endometrial thickening is only considered when it exceeds 20mm. At this time, if the endometrial thickness of 8mm, also belongs to the normal situation; 2, after menopause: endometrial thickness of 8mm, belongs to the endometrial thickening. Because the thickness of the endometrium after menopause is generally defined as 5mm, more than 5mm is considered endometrial thickening. It is usually necessary to further investigate the cause and give treatment. Hysteroscopy and cervical biopsy are often needed to confirm the diagnosis, which is usually associated with endometrial polyps, endometrial hyperplasia and endometrial cancer. If endometrial polyp is present, surgical removal is required. If there is endometrial hyperplasia, progestin therapy needs to be given. If endometrial cancer is diagnosed, surgical treatment combined with radiotherapy and chemotherapy is required.