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The Boston Globe

Nation

Earlier puberty seen in boys, just like in girls

CHICAGO — When it comes to the birds and the bees, parents may want to have that talk with their boys sooner than they expected.

Researchers have found signs of puberty in US boys up to two years earlier than previously reported — age 9 on average for blacks, 10 for whites and Hispanics. Other studies have suggested that girls, too, are entering puberty younger.

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Why is this happening? Theories range from higher levels of obesity and inactivity to chemicals in food and water, all of which might interfere with normal hormone production. But those are just theories, and they remain unproven.

Dr. William Adelman, an adolescent medicine specialist in the Baltimore area, says the new research is the first to find early, strong physical evidence that boys are maturing earlier.

The study was published online Saturday in Pediatrics to coincide with the American Academy of Pediatrics’ national conference in New Orleans.

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