Menstrual period generally refers to menstruation. Reasons for not having menstruation with a 10mm endometrium include pregnancy, or may be due to diseases such as uterine adhesions or polycystic ovary syndrome. 1. Pregnancy: For women in their reproductive years, if they engage in unprotected sex, the endometrium thickness of 10mm, but not menstruation. The first thing to consider is that it is due to pregnancy. 2. Uterine adhesion: Uterine adhesion may be caused by trauma, infection, low estrogen level, heredity and other factors. The patient will have abnormal menstruation and amenorrhea, which is manifested by 10mm of endometrium and no menstruation. 3. Polycystic Ovary Syndrome: Polycystic Ovary Syndrome is mainly caused by a combination of genetic and environmental factors. Patients manifested as scanty menstruation, amenorrhea, irregular uterine bleeding, etc., may appear in the endothelial 10mm has not come to menstruation. There are many causes of 10mm endometrium and no menstruation, and patients can find out the causes in time.