There are many reasons for endometrial separation, clinically more common are the following reasons: First, endometrial separation depends on the age, if if the endometrial separation during the reproductive period, more suggests that there is accumulation of blood in the uterine cavity, its cause may be in the menstruation just clean, menstrual blood has not been completely out, at this time through ultrasonography can see the endometrial separation, belongs to the normal physiological phenomenon, with With the shedding of the endometrium over time, the separation in the uterine cavity will disappear. Secondly, the endometrium is separated because the fluid in the uterine cavity cannot flow out completely due to cervical occlusion, which is usually caused by repeated abortions or cervical surgery. Thirdly, like postmenopausal women who may have endometrial separation, a small amount of endometrial separation may occur because there is no normal endometrial exfoliation in the uterus after menopause. If there is no abnormal bleeding clinically, it can be observed regularly first.