Usually the menstrual cycle is considered normal for about thirty days, for example, if the period came on the first day of last month, the cycle will be thirty days if the period comes on the first day of this month, but not all women have their periods on thirty days. Some women do not ovulate regularly enough and may have a period once every 25 days, while some women have a period once every 35 days. Generally, the menstrual cycle is counted from the first day of menstruation to the first day of the next month’s menstruation. It is clinically considered normal to have a menstrual cycle of about thirty days on weekdays, and some women have a menstrual cycle that is seven days early or seven days late. Therefore, women with periods not exceeding seven days and cycles of about one month are considered normal. When this range is exceeded, menstrual disorders are considered and the cause should be checked at the hospital. It is recommended that during menstruation you should ensure sufficient sleep, avoid staying up late, avoid strenuous exercise, and use good quality sanitary napkins to prevent infection and inflammation. Also do a good job of pubic hygiene and avoid intercourse.