Dr. Dianne Deplewski, a pediatric endocrinologist at the University of Chicago, has not seen any increase in boys referred to her for signs of early puberty. She said it's possible that the new study results were skewed by families who brought their boys to the doctor because they already had concerns about their health.
The study had other limitations. Testes were measured just once, and doctors weren't randomly recruited but volunteered to participate. That means it's possible that those with early maturing patients were overly represented, but Herman-Giddens said it's unlikely boys in the study were different from those in the general U.S. population.
She said the research methods weren't perfect but that they're the best to date. She also stressed that the results shouldn't be used to establish a "new normal" for the start of puberty in boys.
"Just because this is happening doesn't mean this is normal or healthy," the researcher said.
AP Medical Writer Lindsey Tanner can be reached at http://www.twitter.com/LindseyTanner
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