Precocious puberty is diagnosed when a girl develops secondary sexual characteristics before the age of 8 or has the first menstruation before the age of 10. The first clinical manifestation of girls is breast development, with nucleus formation and localized elevation into small mounds, while nipples and areolas gradually increase in size. The internal and external genitalia are enlarged, pigmentation of the labia minora, white vaginal discharge, redistribution of subcutaneous fat, early age of menarche, and possibly ovulation of menstruation. Most of the pubic hair appears about one year after breast development, while the axillary hair appears later, often after menarche.
. Precocious puberty in boys is defined as: secondary sexual characteristics appear before the age of 9 years and progress rapidly, but the progression of sexual development is similar to normal pubertal development.
Accelerated height growth is the earliest sign of sexual development, but is often overlooked. Subsequently, testicular enlargement appears, which is an important feature of the manifestation of true precocious sexual signs in males. Further penile growth, scrotal enlargement, increased scrotal skin folds, deepening of pigmentation, pubic hair growth, increased penile erection, and seminal emission are present. The sequence of the appearance of male secondary sexual characteristics such as axillary hair, beard, throat knot and voice change is also similar to that of normal pubescent children, only at an earlier age. Children with precocious puberty often temporarily exceed the height of children of the same age. However, due to the premature secretion of estrogen or testosterone, the epiphysis closes early, so the growth time of children with true idiopathic precocious puberty is shortened, which affects the height of adults and causes dwarfism; in addition, girls are mainly with idiopathic precocious puberty, while boys are mainly with organic lesions. Therefore, once the child is found to have early development, it is important to seek timely medical attention.