Many parents believe that it is normal for children to develop early and be tall because of good nutrition nowadays. However, they do not know that these phenomena may not be a good thing. If the early growth is caused by precocious sexual maturity, it will affect height development and eventually cause short stature as an adult. 1, normal sexual development Under normal circumstances, girls usually appear in more than ten years old when the development of secondary sexual characteristics, such as breast development, pubic hair growth, menstruation, etc.. For boys, testicular development, beard growth and other secondary sexual characteristics begin to appear at the age of 12 or 13. If a girl develops breasts before the age of 8 and a boy develops testicles before the age of 9, it is precocious sexual maturity. 2. What is precocious sexual maturity Clinically, precocious sexual maturity is divided into true precocious sexual maturity and pseudo precocious sexual maturity. True precocious puberty, also known as central precocious puberty (CPP), refers to the early activation of the human hypothalamus-pituitary-gonadal axis function, the hypothalamus increases the secretion and release of gonadotropin-releasing hormone in advance, leading to gonadal development and secretion of sex hormones, resulting in the development of internal and external genitalia and the presentation of secondary sexual characteristics and functional maturity. Pseudo precocious puberty means that the development of secondary sex characteristics is not in line with the pace of gonadal development, while the testes or ovaries themselves are not developed, but some secondary sex characteristics appear in advance. 3. Factors causing precocious sexual maturity The known causes include: environmental pollution, consumption of food and drugs containing sex hormones, other diseases, genetic factors, excessive exposure to light, media transmission, etc. According to another research report, precocious puberty is related to the modern diet that favors high fat, high protein, etc., and is caused by overnutrition or overweight. 70-80% of precocious puberty in girls is unexplained and somatic. In contrast, more than 50% of boys can find the cause, such as brain tumors. 4, the hazards of precocious sexual maturity Precocious sexual maturity can cause both psychological and physical harm to children. The child may have low self-esteem, fear and anxiety because he or she is different from his or her surrounding partners in terms of body shape and appearance. Early menstruation in girls often affects their normal life and studies. Boys may develop a tendency for early love and premature sexual behavior. Because precocious children are often accompanied by accelerated skeletal growth, although they seem to grow faster than others for the time being, they use up the parts that are going to grow later early. The vast majority of precocious puberty can be cured, but early detection and timely treatment are very important. As long as early detection and timely treatment, patients with precocious puberty can obtain a normal psychological state and the desired adult height, and the earlier the treatment, the better the results.