Color ultrasound shows that the thickness of endometrium is 11mm, which is normal if it is premenstrual or during menstruation; if it is postmenstrual, it is abnormal and belongs to thickening, which needs to be checked and treated. 1. Before and during menstruation: the thickness of women’s uterine lining will change because of the menstrual cycle, and will continue to thicken because of the development of follicles, and the normal value of the uterine lining is between 4-12 millimeters, and the endometrial thickness of women in the luteal phase of the uterine lining is between 10mm~12mm, so 11mm is normal. 2. Postmenstrual: women’s endometrial thinning after menstruation, generally between 4mm ~ 7mm, so 11mm is not normal, it is necessary to go to the regular hospital to receive examination, according to the cause of treatment. In addition, the thickness of the endometrium plays a vital role in women’s reproductive health, so there are problems that need to be actively examined and treated.