Adolescence is a process from childhood to adulthood. During this process, important physical and mental changes occur in children. In general, the first sign of puberty is enlargement of the breasts in girls and the onset of growth in the testicles in boys. Later, pubescence and other signs appear.

The puberty period begins with the effect of hormones secreted from the pituitary gland, and as a result of the increase in the level of sex hormones , it provides the appearance of physical characteristics specific to that gender.

During adolescence, there is an acceleration in height growth, and at the end of this period, the epiphyses close and growth stops. Puberty symptoms begin between the ages of 8–13 (average age of 11–11.5 years) in girls and 9–14 (average age of 11.5–12 years) in boys.

The appearance of puberty before the age of 8 in girls and before the age of 9 in boys is called "Early puberty." This usually occurs as a result of puberty hormones being activated prematurely.

While there is a serious underlying problem that may cause this in some cases, in other cases there may be only a pituitary timing error. Whatever the cause, precocious puberty is a condition that affects both the mental and physical development of the child. Sometimes the age of onset of puberty is normal, and its progression can be very rapid.

In both cases, bone age progresses rapidly, leading to premature growth arrest and short stature. These children should be evaluated without delay in terms of both the underlying cause and treatment.