For parents, they are more concerned about their children’s height, such as how tall their children can still grow, and whether their children are short now is a late growth? What is late growth? First of all, before understanding what is late growth, let’s understand two concepts “bone age” and “bone age difference”. 1, bone age: we usually say age refers to the actual age, bone age is a developmental age obtained by comparing the actual degree of bone development of children and adolescents with the standard degree of development, bone age is more accurate than the actual age to determine the degree of maturity of the human body. 2.Bone age difference: bone age difference is the difference between age and bone age, which is the specific number of years difference between the two. (1) Usually ± 2 years as the normal range of bone age difference, where the bone age difference within ± 1 year is normal; (2) bone age greater than age 1 year but not more than two years is early; (3) bone age less than age 1 year but not more than two years is late; (4) bone age behind the age of more than 2 years is considered abnormally backward; (5) if the bone age in advance of the age of more than 2 years, it is considered abnormally early bone age. Next is to understand what is late growth: late growth is a type of normal growth, late growth of the child puberty fierce growth and sexual maturity time appears late, but when the end of puberty of the same age, after the growth plate healing, these children are just in puberty, still growing, so the final height is no different from the general adult. No treatment is usually needed. What are the outward signs of late growth? It often manifests itself as normal appearance, short stature and lagging bone age. Both parents are of normal height, but the child grows slightly slower each year, is short in stature during childhood, and lags behind the actual age in bone age. The mechanism for this is not fully understood, but there is usually a family history of “late growth”. For example, the father does not grow until after high school or college. Mothers have their first menstrual period after the age of 15-16. How can I tell if my child is a late bloomer? What tests are needed? 1. Bone age film: to determine the skeletal age of the child and provide a basis for further determination of the child’s condition; 2. Thyroid function: to exclude hypothyroidism; 3. Growth hormone stimulation test: to exclude growth hormone deficiency (pituitary dwarf); 4. Saddle area nuclear magnetic: to exclude pituitary dysplasia leading to short; 5. Blood chromosome: to exclude growth retardation and chromosomal disorders; 6. Relevant sex hormone examination: puberty Delayed onset to rule out gonadotropin deficiency.