It is normal for women to menstruate between the ages of 11 and 16, and clinical attention should be paid to those who have not yet menstruated after the age of 16. A woman’s first menstrual period is called menarche. The first menstrual period occurs between the ages of 13 and 14 in most cases, but some people may have their first menstrual period as early as 11 years of age, while some may have their first menstrual period as late as 16 years of age. The timing of menarche is affected by a variety of factors, with genetics being the main influence and other factors such as nutrition and body weight also playing a significant role. In recent years, there is a tendency for women to start menstruating earlier. However, if menstruation does not occur after the age of 16, it is important to pay attention to the problem and go to the gynecology clinic of your local hospital to find out the cause of the problem and get the right treatment.