When a young child begins to undergo the physical changes that normally occur in the early teens, the condition is known as precocious puberty. Although rates of sexual maturation differ from person to person, it is generally agreed that puberty beginning before age eight in girls and age nine-and-a-half in boys is abnormal. In most cases of precocious puberty, an underlying cause can be found and treated. Girls are five to seven times as likely to develop precocious puberty as boys.
WHEN SHOULD I SUSPECT THAT MY CHILD IS DEVELOPING PRECOCIOUS PUBERTY?
The most telling signs are development of what are known as secondary sex characteristics—breasts, pubic hair and menstruation in girls, and pubic hair, enlarged penis and testicles, facial hair and vocal deepening in boys. In addition, children undergoing precocious puberty enter a period of rapid growth and weight gain similar to that of normal adolescence when the bones harden and mature. The difference, though, is that these children have not completed the growth of their early years, and when their bones harden, growth stops.
HOW DOES PRECOCIOUS PUBERTY DEVELOP?
The changes of puberty are triggered by the pituitary, a pea-sized gland near the base of the brain, and the nearby hypothalamus. Often, precocious puberty results from a problem in these two powerful glands, which are somehow turned on ahead of schedule. As a result, affected children have elevated levels of sex hormones.
No cause can be found for many cases of precocious puberty. Sometimes, precocious puberty in either sex is due to a hormone-secreting tumor in the pituitary or hypothalamus.
Precocious puberty also may accompany chromosomal disorders, including Down's syndrome or untreated hypothyroidism (an underactive thyroid gland).
A form of precocious puberty called medicational precocity results from accidental exposure to estrogen in drugs or food. Medicational precocity consists mainly of breast development, which can occur in both girls and boys who have taken estrogen.
Children can be exposed to estrogen by ingesting birth control pills or estrogen-replacement medication. In addition, some nonprescription creams advertised as bust developers contain enough estrogen to affect a child who comes into repeated contact with them.
On a few occasions, estrogen given to livestock also has caused breast development in children. Several occurrences of abnormal breast development among children in Puerto Rico a few years ago were linked to chickens fed estrogen.
IS MEDICAL ATTENTION NECESSARY?
Yes. Any girl who shows signs of sexual maturation before age eight (and any boy who begins to mature before age nine-and-a-half) should definitely see a doctor. Slightly older children entering puberty also could benefit from a doctor's attention, if only for reassurance.
Unless premature puberty is halted, growth of the long bones will cease too soon, resulting in short stature. One-third of children who enter puberty precociously are under five feet tall as adults.
HOW CAN THE DOCTOR TELL IF MY CHILD IS DEVELOPING PRECOCIOUS PUBERTY?
A doctor can usually observe precocious puberty on physical examination. The parents may be questioned to rule out problems that may mimic precocious puberty—for example, a recurrent vaginal infection that causes menstrual-like bleeding. Possible sources of medicational precocity also may be uncovered in such an interview.
Blood and urine tests are performed to detect elevated levels of sex hormones. X rays, particularly of the wrist and arm, can show whether the bones are hardening. Both these changes indicate that the problem involves the pituitary, hypothalamus or both. Special imaging tests (CT or MRI scans) are performed to detect tumors in the pituitary, hypothalamus, liver, ovary or testes. These scans should be repeated periodically, because pituitary and hypothalamic tumors grow slowly and may not be detectable until a year or two after precocious puberty appears.
WHAT TREATMENTS ARE AVAILABLE?
Surgery and radiation are the main treatments employed against tumors that trigger precocious puberty. In addition, powerful new drugs called LHRH analogs can reverse the signs of precocious puberty. These drugs reduce the secretion of sex hormones as soon as two weeks after treatment begins, and symptoms begin to disappear soon afterward.
GETTING HELP
Call your doctor if your child:
• Shows any signs of early sexual maturation
• Seems to be growing and gaining weight too quickly
