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.
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.
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:
Puberty is called precocious in African American girls if they develop breasts before they are 5 or 6 years old. It is called precocious in Caucasian girls if they develop breasts before they are 6 or 7 years old. Precocious puberty is much more common in girls than it is in boys.
African American and Caucasian boys both start puberty at about 9 years old. Puberty is called precocious for them if they begin sexual changes before this time.
Children with CPP grow quicker than normal. Children with isolated, partial forms of precocious puberty, on the other hand, usually grow normally. In male CPP, the testicles enlarge before the penis begins to enlarge. In PPP, the penis grows much larger than the testicles.
Mental development is usually the same as other children their age. Mood swings are not uncommon, but serious psychological problems are unusual.
Other special conditions that may be seen include the following:
Diagnosis of precocious puberty begins with a medical history and physical exam. The healthcare provider may order tests, including:
Other tests may be ordered to verify suspected underlying disorders.
Precocious puberty cannot be prevented.
Some forms of precocious puberty cause the skeleton to mature quickly. At first, these children are taller than their peers. However, growth stops early for these children. Without treatment, they may end up being very short adults. Other long-term effects depend on the underlying conditions identified.
Precocious puberty is not contagious and poses no risk to others.
Children with CPP may be treated if their bone age is 2 years more advanced than their chronological age. Injections of long-acting GnRH agonists, such as histrelin, can be given. These injections cause sexual development to stop. The normal growth rate returns. Girls can be given this treatment until they are between 11 and 12 years old. Boys can be given this treatment until they are between 12 and 13 years old.
Children who have precocious puberty for reasons other than CPP need to have the primary disorder treated. This can include:
Some girls with CPP will have vaginal bleeding about 2 weeks after the first injection of a GnRH agonist. This bleeding usually does not recur.
Because their growth and sexual development is advanced, some children with precocious puberty may feel isolated from their peer group. Frank and early discussion about their condition and body image may be reassuring. Parents and other concerned adults should be alert to signs that the child is having difficulty coping.
Any new or worsening symptoms should be reported to the healthcare provider.
Author:John Wegmann, MD
Editor:Ballenberg, Sally, BS
Reviewer:Barbara Mallari, RN, BSN, PHN