Bone age normal breast development, depending on whether it is precocious puberty and then decide whether to interfere, if it is precocious puberty should be timely interference, if not precocious puberty do not need to interfere. 1. Normal breast development: puberty refers to the period of transition from childhood to adulthood, in which the secondary sexual characteristics of boys and girls begin to develop, including the growth of pubic hair, the appearance of the boy’s throat knot, the girl’s mammary glands develop and so on, the girl’s puberty is 10 to 18 years old, and mammary glands develop and the appearance of menarche between the ages of 9 to 15 years old is normal, the development of the breasts of this age without the need to intervene. 2. Precocious puberty: The current definition of precocious puberty is the appearance of secondary sexual characteristics before the age of 8 for boys and 9 for girls, and precocious puberty is divided into true precocious puberty and pseudo-precocious puberty, the difference is that true precocious puberty will be ovulation or spermatozoa, and should be treated according to the classification of precocious puberty and the cause of the disease. If your breasts are developing at a normal age, you should consult a doctor in time for a professional examination to determine whether intervention is needed.