A study indicates that boys are experiencing the onset of puberty as soon as two years earlier than reported in previous research.

The 2012 study from researchers at the American Academy of Pediatrics found that boys in the United States were entering puberty six to two months earlier than previous research suggested. While a trend toward earlier onset of puberty in girls has long been studied and accepted, the AAP study was the first to examine the onset of puberty in boys in contemporary times.

The study found that African American boys were more likely to start puberty early than white or Hispanic boys, with the earliest stage of puberty occurring in some non-Hispanic African American boys at age 9.14 years.

The causes and public health implications associated with an earlier onset of puberty require further study, but parents of young boys can benefit from knowing that their sons might be entering puberty earlier than their parents might have expected.