When a child has her period at 11 years old, she can usually still grow about 4 to 8 centimeters taller, with individual differences. In girls, secondary sexual characteristics usually begin to appear around the age of 9, starting with the development of the mammary glands. Breast development is generally the peak growth period until the onset of menstruation, and can grow 6 to 8 centimeters per year, or even more. After the child’s first menstruation at around 11 years of age, the girl’s growth rate slows down significantly until the epiphyses close. After the first menstruation, the total growth space is usually about 4 to 5 centimeters, there are more obvious individual differences, some children can grow more. So the child is 11 years old menstruation, still can grow taller, but because the total growth space is smaller, this time need to strengthen physical exercise, appropriate supplement protein and calcium to enhance nutrition.