The endometrium will change with the menstrual cycle and will reach its thickest before the menstrual period, at around 10-12mm. When not in menstruation, the endometrium should be less than 10mm. 25mm endometrium has a chance of endometrial cancer, but it is not necessarily cancer. Consider endometrial hyperplasia, which appears as simple hyperplasia, atypical hyperplasia or complex hyperplasia of endometrium, and should be scraped to help diagnose the type of disease. Endometrial cancer is most common in menopausal women. The onset of the disease is associated with thickening of the endometrium, abnormal vaginal bleeding, and in non-menopausal women, increased menstrual flow and menstrual disorders, as well as foul odor when infection occurs. Endometrial cancer is likely to occur in women with obesity, high blood pressure, diabetes, infertility or delayed menopause, and annual gynecological checkups should be performed for good health.