When you first get your period, it is possible that it will be more regular 2-3 years later. Although the uterus and ovaries are well developed at this time, they are not fully functional, so many people do not have regular menstruation after their first period. But clinically, the time is not the same, many people have regular periods after the first time, and some people have regular periods for about a year after the first time, and fewer people may have longer periods. Menorrhagia may occur after the first menstruation, and the second menstruation may occur after half a year, and then it will gradually become regular within the range of 2-3 years.