A few days of normal menstrual cycle

Generally, women's menstrual cycle is 28 days, menstrual duration is one week, and ovulation day is 14 days before the next menstrual period. However, due to the influence of female endocrine, endocrine is affected by many factors such as life and diet, so most women's cycles are different. Generally, as long as the cycle is longer or shorter within one week, it is considered normal.