What is puberty?
Puberty is the time of life when a child develops into an adult. It usually begins between the ages of 8 and 13 in girls and between 9 and 14 in boys.
Puberty involves:
- The development of the gonads (e.g., ovaries in girls and testes in boys).
- The development of secondary sex characteristics (e.g., growth of underarm and pubic hair, breast development, and penile and testicular growth).
- Growth spurts of bones and muscles.
- Changes in body shape and size.
The main hormones responsible for puberty are gonadotropins and sex steroids (testosterone and estrogen). Puberty happens under the control of a complex system known as the hypothalamicpituitary - gonadal (HPG) axis.
A part of the brain called the hypothalamus releases gonadotropin-releasing hormone (GnRH). This hormone stimulates the pituitary gland to release two gonadotropins: luteinizing hormone
(LH) and follicle-stimulating hormone
(FSH). These gonadotropins then stimulate the gonads to produce sex steroids—estrogen in females and testosterone in males—that lead to the physical changes of puberty.
The adrenal glands also play a role in the production of sex steroids, but their role is usually less important than that of the gonads.
What is precocious puberty?
Precocious puberty is traditionally defined as the appearance of any sign of secondary sexual characteristics in boys younger than 9 and in girls younger than 8. However, in most of these children the early puberty is a variation of normal and no medical problem is present. Just as there are differences in the age at which puberty starts, there are also differences in the speed at which a child goes into puberty. Children who experience puberty too early (early bloomers) or too late (late bloomers) often have a family history of this developmental timing.
Near the end of puberty, growth in height stops. Because the bones of children with precocious puberty mature and stop growing at an earlier age than normal, they can be shorter than expected as adults. Precocious puberty can also cause emotional and social problems for children who are ahead of their peers in terms of sexual maturity.
What causes precocious puberty?
Not all forms of precocious puberty are dangerous. For example, premature thelarche refers to isolated breast development in very young girls, while premature adrenarche refers to isolated pubic or axillary hair in boys and girls. These are poorly understood but do not represent an underlying medical condition.
There are two types of precocious puberty that can be dangerous. The first is called central precocious puberty .(CPP) and the second is peripheral precocious puberty .
(PPP).
CCP is caused when the hypothalamus releases GnRH and activates the HPG axis (or puberty) early. In most girls with CPP, there is no underlying medical problem. In boys, the condition is less common and is more likely to be associated with a medical problem such as a tumor, brain trauma (e.g., a blow to the head, surgery, radiation treatment), or inflammation (e.g., meningitis).
PPP, which is more rare, is caused by too much production of sex steroids (estrogen and testosterone) due to problems with the ovaries, testicles, or adrenal glands. It can also be caused by external exposure to sex hormones (e.g., coming into contact with an estrogen or testosterone cream.)
How is precocious puberty diagnosed and treated?
Treatment of precocious puberty will depend on whether it is CPP or PPP. To make a diagnosis, your doctor will take a medical history, do a physical exam, take blood tests to measure hormone levels and obtain x-rays (if necessary) to see if bones are maturing too fast. Sometimes a “stimulation” test is performed to find out if the puberty has been activated. Also, a CT scan or MRI to check for a tumor is often ordered.
Treatment of precocious puberty will depend on whether it is CPP or PPP. To make a diagnosis, your doctor will take a medical history, do a physical exam, take blood tests to measure hormone levels and obtain x-rays (if necessary) to see if bones are maturing too fast. Sometimes a “stimulation” test is performed to find out if the puberty has been activated. Also, a CT scan or MRI to check for a tumor is often ordered.
If it’s CPP, there are medications (for example, leuprolide acetate) to control the HPG axis and prevent further pubertal development.
If it’s PPP, the treatment will depend on the cause and could involve medications, surgery (if there is a tumor), or removing the external source of the hormones (e.g., estrogen cream).
What should you do with this information?
If your child has any of the signs of precocious puberty, consult a pediatric endocrinologist, an expert in the treatment of hormone-related conditions in children. Precocious puberty requires attention to ensure that there is no underlying cause.
Your doctor will work with you to determine the best treatment option.
