Girls enter puberty between the ages of 8-14. Boys enter this stage between the ages of 9-14. Sometimes the physical changes may happen earlier. This is called precocious sexual development or premature puberty.

For girls, this means that before the age of eight they may:

  • Develop breasts
  • Have armpit or pubic hair
  • Have mature sex organs
  • Experience their first period
For boys, this means before the age of nine they may have:
  • Enlarged sex organs
  • Armpit, pubic, or facial hair


Most of the time (ie, 90%) there is no known cause. With boys, between 25%–75% of these cases are due to an underlying reason.

Some known causes of premature sexual development:

Pituitary Gland

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Causes specific to girls:

  • Having ovarian tumor or ]]>cysts]]>
  • Taking estrogen
Causes specific to boys:

  • Having tumors on the testicles
  • Taking male sex hormones (androgens)

Other causes:


Risk Factors

Factors that increase the risk of precocious puberty include:

  • Sex: girls are 2 to 5 times more likely to experience premature puberty than boys
  • Family history—some cases may run in families
  • Taking sex hormones
  • Head injury
  • Radiation of head
  • Infection in brain
  • Some studies have suggested a link between obesity]]> and premature puberty


One symptom common to both boys and girls is a premature growth spurt in height. Children with this condition may be taller than their peers. As an adult, they may be shorter. The rapid growth also makes their bones stop growing sooner than normal. Other symptoms include:

  • In girls:
    • Breast development
    • Pubic hair
    • Armpit hair
    • Onset of period
    • Ovary enlargement
    • Cysts on ovaries
  • In boys:
    • Facial hair
    • Armpit hair
    • Pubic hair
    • Penis growth
    • Increased masculinity
    • Testicle enlargement
  • In both girls and boys:
    • Body odor
    • Acne]]>
    • Behavior changes
    • Growth spurt



The doctor will ask about your child’s symptoms and medical history. A physical exam will be done. An assessment of puberty milestones and growth will be done. An x-ray]]> of the left wrist bone may be taken. This will help to assess if bone growth is normal for your child’s age.

Depending on these results, other tests may be ordered, including:

  • Adrenal and ]]>pelvic ultrasound]]>
  • ]]>MRI]]> of the brain
  • Hormonal levels:
    • In girls: follicle-stimulating hormone (FSH), luteinizing hormone (LH)
    • In boys: testosterone
  • Human chorionic gonadotropin (hCG) levels
  • Thyroid hormone levels if hypothyroidism suspected
  • Growth hormone-releasing hormone (GHRH) stimulation test
  • Dehydroepiandrosterone (DHEA) levels
  • Testicular ultrasound if testicular enlargement is uneven



The treatment depends upon the cause. If the bone age is about the same as their actual age, and there is no known cause, there is no treatment. The child will continue to be monitored.


Hormone suppressors work by halting or slowing sexual development. These medications may include:

This treatment is often used in children whose bone age is older than their actual age. These medications stop sexual development. They also halt the rapid bone growth. This will allow for normal bone growth.

]]>Metformin]]> has also been shown to be effective in delaying puberty.

Psychological Support

Support may be valuable for children who are more physically mature than their peers.


Hormone-producing tumors or other lesions may cause premature puberty. They are usually removed with a surgery.

Ongoing Monitoring

The doctor will continue to monitor your child’s height, weight, and sexual development. This will chart the progress. It will also show if any given treatment has been effective.


Most cases cannot be prevented. To help reduce the chance, make sure your child is kept as healthy as possible. This includes making sure they are eating well and getting all the nutrients they need. Help your child maintain a healthy weight. Avoid exposure to sex hormones.