Auntie is the common name for menstruation. It is usually normal for a girl to get her period at the age of 12. A girl’s reproductive system develops as she ages. A girl’s period occurs when the hormones produced by the ovaries produce cyclical changes that cause the uterine lining to shed. The first menstrual period usually occurs between the ages of 12 and 15. The onset of menstruation means that a girl has reached puberty and her reproductive system is functioning at a basic level. However, at this age, girls often have irregular menstrual cycles because they are not yet mature. Parents or teachers can explain basic physiological knowledge to girls at the beginning of menstruation. In addition, girls should take rest and avoid strenuous exercise when menstruating.