Puberty is a time when the body changes and is able to reproduce for the first time. Precocious puberty is a condition in which these changes occur earlier than normal.

What is going on in the body?

Hormones are released during puberty that foster physical growth and sexual development. The primary sexual changes that occur during puberty are the growth and maturation of the ovaries in girls and the growth and maturation of the testicles in boys. The secondary changes include the following:

Precocious puberty occurs when the sexual hormones are released early. This is known as CPP, or central precocious puberty. With CPP, sexual changes occur in the normal order seen in puberty.

PPP, or peripheral precocious puberty, occurs when other conditions trigger the early production and release of sexual hormones. With PPP, sexual changes may not occur in the normal order seen in puberty.

Partial forms of precocious puberty are fairly common. Girls may develop breasts prematurely without other changes. Boys or girls may have sexual hair early, without other changes.

What are the causes and risks of the condition?

No underlying cause of precocious puberty can be found in 85% of girls and 40% of boys.

For the remaining children, causes may include:

Precocious puberty can also be inherited. In a family where one parent carries the gene, there is a 50% percent chance that male infants would be affected. Female infants would have a 50% chance of being a carrier for the gene.

Estrogen can cause premature sexual changes, like breast development, that can look like precocious puberty. These precocious changes go away after the estrogen exposure is stopped. Estrogens are found in the following: