The normal menstrual cycle runs from the first day of menstruation to the first day of the next menstrual period and is called the menstrual cycle. Everyone’s menstrual cycle varies in length and is not fixed, with the majority of people having a 28-30 day cycle. It is also normal if your menstrual period is 3-4 days early, i.e. 25-26 days per cycle. Because the menstrual cycle is also affected by emotions, diet, work and rest patterns and other factors, if the menstrual cycle is very regular, each menstrual cycle is 25-26 days, it is a normal physiological phenomenon, and do not need to worry. However, if there are changes in the menstrual cycle, within 20 days or more than 45 days in advance, or if there are abnormalities in the amount of menstruation, it is necessary to go to the hospital for consultation.