Endometrial thickening may cause menstrual bleeding and irregular vaginal bleeding, and some patients may have menstrual disorders and other related symptoms. Endometrial thickening may be physiologic, such as endometrial thickening during the premenstrual period, and as hormone levels drop, the endometrial lining will retreat and bleed, resulting in menstrual bleeding. Endometrial thickening can also be pathologic, also known as endometrial hyperplasia, and is considered to be related to oral contraceptive use, postmenopausal estrogen supplementation therapy, and obesity. Early symptoms are less obvious, and as the disease progresses there may be abnormal uterine bleeding, shortened and prolonged periods, and non-menstrual vaginal bleeding. When women have endometrial thickening, they will have vaginal bleeding, but they need to cooperate with the doctor to identify whether it is physiological or pathological, and then deal with and treat it.