Girl, you'll be a woman sooner than expected
Puberty is arriving ever younger in American females -- 8 is no longer considered abnormal.
By Susan Brink January 21, 2008
AT 8 or 9 years old, the typical American schoolgirl is perfecting her cursive handwriting style. She's picking out nouns, verbs, adjectives and adverbs in sentences, memorizing multiplication tables and learning to read a thermometer
She's a little girl with a lot to learn.
And yet, in increasing numbers, when girls this age run across the playground in T-shirts, there is undeniable evidence that their bodies are blossoming. The first visible sign of puberty, breast budding, is arriving ever earlier in American girls.
Some parents and activists suspect environmental chemicals. Most pediatricians and endocrinologists say that, though they have suspicions about the environment, the only scientific evidence points to the obesity epidemic. What's clear, however, is that the elements of female maturity increasingly are spacing themselves out over months, even years -- and no one quite knows why.
While early menstruation is a known risk factor for breast cancer, no one knows what earlier breast development means for the future of girls' health. "We're not backing up all events in puberty," says Sandra Streingraber, biologist and visiting scholar at Ithaca College. "We're backing up the starting point." She has examined the research on female puberty and compiled a summary in an August 2007 report called "The Falling Age of Puberty in U.S. Girls." The report was financed by the Breast Cancer Fund, an advocacy group interested in exploring environmental causes of that disease.
Earlier breast development is now so typical that the Lawson Wilkins Pediatric Endocrine Society urged changing the definition of "normal" development. Until 10 years ago, breast development at age 8 was considered an abnormal event that should be investigated by an endocrinologist. Then a landmark study in the April 1997 journal Pediatrics written by Marcia Herman-Giddens, adjunct professor at the School of Public Health at the University of North Carolina, Chapel Hill, found that among 17,000 girls in North Carolina, almost half of African Americans and 15% of whites had begun breast development by age 8. Two years later, the society suggested changing what it considered medically normal.
The new "8" -- the medically suggested definition for abnormally early breast development -- is, the society says, 7 for white girls and 6 for African American girls.