Frequent urination during menstruation is mainly caused by the irritation of the urethra caused by the menstrual blood. The urethra of women is clinically short and straight, and the stimulation of menstrual blood during menstruation can also cause frequent urination in some people who are more sensitive. Changing sanitary napkins regularly during menstruation and drinking more water and repeatedly flushing the urethra after drinking more water will also make the frequent urination improve. It is recommended to use cotton sanitary napkins to avoid poor local ventilation to make menstrual blood aggravate the irritation of the urethra. When you have your period, you should wash your vulva 1-2 times a day to keep it locally clean, which will also reduce the irritating symptoms of the urethra.