When Does Menstruation Typically Begin? Age & Development

The average age for girls to get their first period is between 12 and 15 years old, but it can happen as early as 8 or as late as 16. Periods usually start between 2 and 3 years after a girl's breasts start to develop. Many girls get their first period while they are in middle school, but some may get it while they are still in elementary school or after they have started high school.