Precocious puberty is the early onset of sexual maturity as evidenced by physical and emotional changes. It occurs in girls before the age of 8 years, and in boys before the age of 9 years. The condition is more common in girls than in boys.

Puberty is a period of developmental transition between childhood and adulthood that marks the beginning of the process that eventually culminates in a person’s ability to reproduce. Girls typically begin the maturation process around the age of 10 years, whereas boys mature around age 12. Children who experience precocious puberty mature earlier than their peers.

During precocious puberty, an area of the brain called the hypothalamus signals the pituitary gland near the base of the brain to release hormones that start sexual development. In most cases, the cause of early puberty is unknown and is not related to a health condition. However, illness and injury can sometimes trigger precocious puberty. Examples of such factors include tumors that secrete hormones, other structural problems in the brain, brain injuries, and infections such as meningitis.

Some of the signs of precocious puberty depend on the child’s gender. Signs for girls include breast development and the onset of menstruation. Boys may experience enlargement of the testicles or penis and a deepening of the voice. Both genders tend to have rapid growth spurts, growth of hair under the arms and in the pubic area, acne and “adult” body odor. Because bone growth occurs during puberty, some children with precocious puberty may require treatment with medications to reach adult stature.

Parents are urged to bring their child to a physician if the child shows signs of puberty at an early age. A complete physical examination, thorough medical history, blood and urine tests, and imaging tests all are part of diagnosing precocious puberty.