Before menstruation, there is an increase in vaginal discharge. The increase in estrogen levels in the body before menstruation leads to an increase in leukorrhea secretion. Most of the increased discharge is normal leukorrhea, which is colorless, odorless, sticky and has the effect of lubricating and purifying the vagina. As the menstrual cycle approaches, the discharge will gradually turn brown, mainly due to the further increase of estrogen level in the body, resulting in the onset of menstruation 2-3 days after the appearance of brown discharge. Before menstruation, during ovulation and after menstruation, the increase of vaginal discharge is a normal physiological phenomenon due to the change of hormone level in the body. If the vaginal discharge is not smelly and there is no vulvar itching, no special treatment is needed. Take good care of your vulva, change your underwear regularly and wash your vulva every night to keep it clean and dry.