Menstruation is the common name for menstruation, and the normal age for girls to menstruate is between 13 and 14 years old, as early as 11 years old or as late as 16 years old. If a girl has her period earlier than 11 years old or later than 16 years old, she should seek medical advice and treatment from her doctor. Most girls have their first menstrual period at the age of 13 to 14, but it is mainly controlled by genetic factors, but also related to other factors such as nutrition, weight, etc. It may be as early as 11 years old or as late as 16 years old. The timing of menstruation is largely related to the level of development of the body, and menstruation usually occurs between the ages of 11 and 16. If menstruation does not occur after the age of 16, and the female reproductive organs have not developed, it is necessary to consult a doctor to determine the cause of the problem. Girls in puberty need to be properly supplemented, pay attention to develop a good habit, during menstruation, the diet as light as possible, the first time girls do not need to be overly nervous about menstruation, choose the right sanitary products, maintain local hygiene, to avoid infection. Women’s menstruation is a normal physiological situation, if there is discomfort need to consult a doctor.