Central precocious puberty is mainly seen in two categories: organic lesions of the central nervous system and idiopathic precocious puberty. (1) The common etiologies of organic lesions of the central nervous system include the following categories. 1, acquired: such as brain abscess, cranial radiation therapy, central system inflammation, cranial trauma and surgery, etc. 2, congenital: such as arachnoid cysts, hydrocephalus, hypothalamic malformation, septal-optic nerve dysplasia, cranial suprasellar cysts, etc. 3, brain tumors: such as adenomas secreting luteinizing hormone (LH), astrocytomas, gliomas, etc. (2) Idiopathic precocious puberty: the cause of idiopathic precocious puberty is still unclear. It has been found that most of these patients have sporadic onset, and a few have familial characteristics, and the latter are mostly boys, mainly inherited from their sons by their fathers with a history of precocious puberty, resulting in familial male precocious puberty. Idiopathic central precocious puberty is more common in girls than in boys. There are gender differences in the overall incidence and etiology of precocious puberty in children. The overall incidence of precocious puberty in girls is much lower than that in boys, with a male to female ratio of about 1:4. The incidence of central precocious puberty in girls is also higher than that in boys, with a male to female ratio of about 1:23. The most common cause of central precocious puberty in girls is idiopathic precocious puberty, which accounts for about 80% to 90% of central precocious puberty in girls, including sporadic and familial, with the former accounting for the majority. The pathogenesis of idiopathic precocious puberty in girls is still unclear, and may be related to the disruption of the control of puberty initiation due to certain factors affecting the central neuroendocrine function. Central precocious puberty in boys accounts for less than 30%, and is mostly secondary to various lesions of the central nervous system, accounting for about 60% of precocious puberty in boys, of which the most common is secondary to tumors of the central nervous system, such as malformation tumors, pineal tumors, germ cell tumors, etc. Therefore, before diagnosing idiopathic precocious puberty in boys, careful examination should be performed to exclude secondary precocious puberty due to organic lesions of the central nervous system. The common causes of precocious puberty in females Precocious puberty refers to the development of female secondary sexual characteristics before the age of 9 years, including breast development, accelerated growth, the first appearance of pubic hair and menstruation. The symptoms and signs of precocious puberty can be generalized or localized, while most children enter puberty early in general, a few only show early appearance of breasts or pubic hair. The common causes of this disease are described as follows: 1. Central factors ① Premature maturation of hypothalamic-pituitary-axis function, which is called somatic precocious puberty, refers to true precocious puberty or primary precocious puberty that is found to be abnormal by systematic examination. It accounts for about 90% of all precocious puberty. Due to the premature establishment and secretion of GnRH-Gn pulse release rhythm in the hypothalamic-pituitary-ovarian system, which promotes ovarian follicle development and sex hormone secretion, it can cause early menarche, ovulation and fertility establishment, and the development of secondary sex characteristics according to the procedure and sequence of normal pubertal development, almost all of them are homozygous precocious puberty. ② Hypothalamic-pituitary system diseases, including encephalitis, tuberculosis, meningitis, injury, vascular malformation, cerebral hypoplasia, hydrocephalus, tumors (mesencephalic malformation, glioblastoma, craniopharyngioma, teratoma), pineal tumors, multiple bone fiber dysplasia, the so-called syndrome, etc., destroy the hypothalamic sexual center, block the inhibitory regulation of the pituitary gland by the hypothalamus, causing pituitary gonadotropin The syndrome is a result of the disruption of the hypothalamic center and the inhibitory regulation of the pituitary gland, causing pituitary gonadotropin secretion and precocious puberty. 2, Peripheral factors Most of them are caused by ovarian and adrenal tumors. For example, ovarian granulosa cell tumors, teratomas, follicular membranous cells and primary choriocarcinoma can cause homosexual precocious puberty, while supportive-mesenchymal cell tumors, hilar cell tumors and xanthogranuloma can cause heterosexual precocious puberty. Congenital adrenocortical hyperplasia and adenoma secretion of excessive androgens cause female masculine signs, and heterosexual precocious signs appear after birth and during peri-pubertal period, including accelerated growth, hirsutism, development of laryngeal nodes, clitoral hypertrophy and other signs of masculinity. 3, other factors Clinical observation shows that about 70% of precocious puberty has no cause, either idiopathic or genetic precociousness, or due to environmental factors and food contamination with sex hormones. In addition, precocious puberty can also be manifested as single sex characteristics development, including simple early appearance of breasts, early appearance of pubic hair, incomplete precocious puberty or temporary precocious puberty.