Precocious puberty

Precocious puberty is when a child's body begins changing into that of an adult (puberty) too soon. Puberty that begins before age 8 in girls and before age 9 in boys is considered precocious puberty.

Puberty includes rapid growth of bones and muscles, changes in body shape and size, and development of the body's ability to reproduce.

The cause of precocious puberty often can't be found. Rarely, certain conditions, such as infections, hormone disorders, tumors, brain abnormalities or injuries, may cause precocious puberty. Treatment for precocious puberty typically includes medication to delay further development.

Symptoms Causes Risk factors Complications Prevention

Precocious puberty signs and symptoms include development of the following before age 8 in girls and before age 9 in boys.

Signs and symptoms in girls include:

  • Breast growth
  • First period (menarche)

Signs and symptoms in boys include:

  • Enlarged testicles and penis
  • Facial hair (usually grows first on the upper lip)
  • Deepening voice

Signs and symptoms that can occur in boys or girls include:

  • Pubic or underarm hair
  • Rapid growth
  • Acne
  • Adult body odor

When to see a doctor

Make an appointment with your child's doctor for an evaluation if your child has any of the signs or symptoms of precocious puberty.

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