3 years old 3 months baby bone age 2 years old may be due to obesity, may also be due to precocious puberty, and may be due to congenital adrenocortical hyperplasia caused by different reasons, different treatment methods. 1. Obesity: obese children have excessive adipose tissue, androgens can be converted to estrogen in adipose tissue, and high estrogen levels can promote the maturation and apoptosis of growth plate chondrocytes, leading to pre-mature bone age. Weight loss should be achieved by controlling diet and strengthening exercise. 2. Precocious puberty: children with precocious puberty will also have large bone age due to the increase of sex hormones in the body, and can be treated with GnRH agonists, such as treprostinil, leuprolide and other drugs. 3. Congenital adrenocortical hyperplasia: Because the adrenal cortex can secrete sex hormones, children with congenital adrenocortical hyperplasia will also have symptoms of 3 years old and 3 months old, with bone age 2 years old, and can be treated with drugs such as deoxycorticosterone acetate and hydrocortisone. All of the above drugs need to be treated under the guidance of a doctor, do not self-medication. If the child has the symptoms of 3 years old 3 months baby, bone age 2 years old, please consult a doctor in time to find out the cause, so as not to delay the condition.