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Cook Children's

Cook Children's

801 Seventh Avenue
Fort Worth, TX 76104

682-885-4000


Precocious Puberty

What Is Puberty?

Puberty is when kids develop physically and emotionally into young men and women. Usually, this starts to happen in adolescence:

  • In girls, the average age is 10.
  • In boys, the average age is 11.

What Is Precocious Puberty?

Precocious puberty is when the signs of puberty start:

  • before age 7 or 8 in girls
  • before age 9 in boys

It can be hard for some kids and sometimes is a sign of a health problem.

What Are the Signs & Symptoms of Precocious Puberty?

In girls, signs of precocious (prih-KOE-shiss) puberty include:

  • breast development before age 7 or 8
  • start of menstruation (her period) before age 10
  • rapid height growth (a growth spurt) before age 7 or 8

In boys, the signs of precocious puberty before 9 years of age include:

In girls and boys, some of these can be signs of possible early puberty, but sometimes are normal:

  • pubic, underarm, or facial hair development
  • voice deepening
  • acne
  • "mature" body odor

How Does Precocious Puberty Affect Kids?

When puberty ends, growth in height stops. Because their skeletons mature and bone growth stops at an earlier age than normal, kids with precocious puberty that's not treated usually don't reach their full adult height potential. Their early growth spurt may make them initially tall when compared with their peers. But they may stop growing too soon and end up at a shorter height than they would have otherwise.

Going through puberty early also can be hard for kids emotionally and socially. Girls with precocious puberty, for example, may be confused or embarrassed about getting their periods or having enlarged breasts well before any of their peers. They may be treated differently because they look older.

Even emotions and behavior may change in kids with precocious puberty. Girls can become moody and irritable. Boys can become more aggressive and also develop a sex drive inappropriate for their age.

What Causes Precocious Puberty?

The onset of puberty is normally triggered by the hypothalamus. This area of the brain signals the (a pea-sized gland near the base of the brain) to release hormones that stimulate the ovaries (in girls) or testicles (in boys) to make sex hormones.

Most commonly, especially in girls, precocious puberty is due to the brain sending signals earlier than it should. There is no other underlying medical problem or trigger. This also can often run in families.

Less often, precocious puberty stems from a more serious problem, such as a tumor or trauma. Thyroid or ovarian problems also can trigger early puberty. In these cases, other symptoms usually happen that point to a more serious problem.

Precocious puberty is less common in boys, and more likely to be related to another medical problem. For about 5% of boys, the condition is inherited.

Some very young girls (usually from 6 months to 3 years old) may show breast development that later disappears or may last but without other physical changes of puberty. This is called premature thelarche (thee-LAR-kee) and usually doesn't cause lasting problems.

Similarly, some girls and boys may have early growth of pubic and/or underarm hair or body odor that isn't related to other changes in sexual development. This is called premature adrenarche (ah-druh-NAR-kee).

These kids may need to see their doctor to rule out "true" precocious puberty. But most need no treatment and will show the other expected signs of puberty at the usual age.

How Is Precocious Puberty Diagnosed?

Talk to your doctor if your child shows any signs of early sexual maturation (before age 7 or 8 in girls or age 9 in boys), including:

  • breast development
  • rapid height growth
  • menstruation
  • acne
  • enlarged testicles or penis
  • pubic or underarm hair

To diagnose precocious puberty, the doctor may order blood tests to look for high levels of sex hormones. X-rays of your child's wrist and hand can show whether the bones are maturing too early.

Rarely, imaging tests such as MRIs and ultrasound studies are done to rule out uncommon causes of precocious puberty, such as a in the brain, ovary, or testicle.

How Is Precocious Puberty Treated?

If your child has precocious puberty, the doctor may refer you to a pediatric (a doctor who specializes in growth and hormonal disorders in children) for treatment.

The treatment goals are to:

  • stop or even reverse sexual development
  • stop the rapid growth and bone maturation that can lead to adult short stature or an early start to periods

Depending upon the cause, there are two possible approaches to treatment:

  1. treating the underlying cause or disease
  2. lowering the high levels of sex hormones with medicine to stop sexual development

Sometimes, treatment of a related health problem can stop the precocious puberty. But in most cases, there's no other disease, so treatment usually involves hormone therapy to stop sexual development.

The currently approved hormone treatment is with drugs called LHRH analogs. These synthetic (man-made) hormones block the body's production of the sex hormones that cause early puberty. Positive results usually are seen within a year of starting treatment. LHRH analogs are generally safe and usually cause no side effects in kids.

In girls, breast size may decrease. In boys, the penis and testicles may shrink back to the size expected for their age. Growth in height will also slow down to a rate expected for kids before puberty. A child's behavior usually becomes more age-appropriate too.

How Can Parents Help?

Give your child a simple, truthful explanation about what's happening. Explain that these changes are normal for older kids and teens, but that his or her body started developing a little too early. Keep your child informed about treatment and what to expect along the way.

Also watch for signs that teasing or other problems may be affecting your child emotionally. Common warning signs to discuss with your doctor include:

  • poor grades
  • problems at school
  • loss of interest in daily activities
  • depression

How parents react can affect how well kids cope. To promote a healthy body image and strong self-esteem:

  • Avoid making comments about your child's appearance.
  • Offer praise for achievements in school or sports.
  • Support your child's interests.

The important thing is that doctors can treat precocious puberty. They can help kids keep their adult height potential and limit the emotional and social stress kids may face from maturing early.

Reviewed by: Tal Grunwald, MD
Date reviewed: September 2019