If there is no vaginal discharge, it may be caused by insufficient hormone levels in the body and local lesions of the cervix, as follows: 1. Insufficient hormone levels: for example, insufficient estrogen levels reduce cervical mucus and vaginal discharge will be reduced. It is best to have blood test for sex hormone six. On the second or third day of menstruation, go to the hospital on an empty stomach to have the corresponding test done, mainly to find out whether the ovaries are functioning normally and whether the estrogen level is normal. 2. Local lesions of the cervix: for example, narrowing of the cervical canal, resulting in reduced cervical secretion and vaginal discharge. It is often accompanied by dysmenorrhea in clinical practice, and cervical cancer should also be excluded.