In most cases, the first menstruation of girls is between 11 and 16 years old, so it is a normal physiological phenomenon for girls to have menstruation at the age of 12, and there is no need to worry too much. After menstruation, a girl’s bones will still grow and develop normally, and her height will not stop growing after menstruation, but the speed of height growth and final height needs to be judged by a combination of factors. The appearance of regular menstruation is an important sign of reproductive maturity, and the menstrual period of girls may cause changes in hormone levels, which may have an impact on the growth rate of height, but usually the impact is not significant. The growth of girls’ height is also related to puberty. The growth rate of height slows down slightly in the 1-2 years before puberty, and after girls’ breasts start to develop, their height usually starts to grow faster, reaching a second peak at the age of 13-15, with an average increase of 8-9 cm per year. In addition to this, the development of height in both boys and girls is related to genetic factors, nutritional factors over time, endocrine levels and the level of development in the mother’s womb during fetal life. To determine whether a girl’s height can continue to grow, a bone age test, such as an x-ray, can be performed to see if the epiphysis has closed, which is less likely to happen if it has, but usually can continue to grow if it has not.