Usually 10-year-old girls breasts start to develop will not adversely affect the growth of size, but the short-term increase in the growth rate of height, is a normal situation. Because, under normal circumstances, the age of girls breast development is in 9~11 years old, so, 10-year-old girls breasts began to develop is not an abnormal situation, therefore, will not adversely affect the growth of size, do not need to worry too much. Secondly, the girl’s breasts began to develop that has reached puberty, belong to the performance of the development of secondary sexual characteristics. According to relevant authoritative information, height will increase rapidly at this time, is also one of the important signs of puberty start, the general girl into puberty will increase 5 ~ 7cm per year, can be as high as 9 ~ 10cm, the duration of about 2 ~ 3 years, belong to the normal physiological phenomenon, but the specific height of the growth of the situation, from person to person, can not be generalized. To summarize, 10-year-old girls breasts began to develop when you need to strengthen all aspects of puberty safety and care of general knowledge of the mission. If you feel unwell, you should go to the hospital in time.