In the case of early pubic hair development, pubic hair normally appears in girls a few months after breast development and in boys a few months after penis and testicular development. Then the premature development of pubic hair is diagnosed with the following conditions: 1. Central precocious puberty Also known as true precocious puberty. It is caused by the early activation of the hypothalamic-pituitary-gonadal axis function. In addition to gender-appropriate secondary sexual characteristics, the child also has accelerated growth, increased bone age and reproductive capacity. It is more common in girls than in boys. In girls, breast development and pubic hair appear first, followed by leucorrhea and menstruation, and possibly ovulation. In boys, enlargement of the penis, voice and throat nodes are first noticed, followed by pubic hair, axillary hair, acne, facial whiskers and spermatorrhea; in fact, enlargement of the testes precedes the enlargement of the penis. Most of them are primary, a few are caused by intracranial tumors. 2, peripheral precocious puberty, also known as pseudo-precocious puberty, the hypothalamus-pituitary-gonadal axis is not mature, due to the peripheral tissues produced by sex hormones and the appearance of homosexual or heterosexual precocious symptoms, that is, boys can appear penis, pubic hair, axillary hair and throat nodes, but testicular enlargement, and boys can also appear female secondary sexual characteristics such as female breast; the same girl can have breast development, pubic hair and axillary hair Similarly, girls can have breast development, pubic hair and armpit hair, as well as male secondary sexual characteristics such as beard and enlarged clitoris. Pseudo-precocious puberty does not have the ability to have children. Early breast development can occur at any age before 8 years old, more in girls than in boys, unilaterally, but mostly bilaterally. The enlarged breasts are within 5 cm in diameter, with tenderness, but the nipples and areolas are normal and can subside and then swell up again at a later stage. There is no leucorrhoea, no accelerated height growth or accelerated bone age. Premature pubic hair development: Under normal circumstances, pubic hair appears several months after breast development in girls; in boys, pubic hair appears several months after the development of penis and testicles. The pubic hair can appear at any age in early development, more in girls than in boys. The amount of pubic hair is small, and sometimes there is also axillary hair, but other sex characteristics develop normally. Most of them are caused by the consumption of children’s health food containing hormones.