Girls in the U.S. may be continuing to hit puberty at earlier ages, according to new research.
The findings suggest earlier development than what was reported in a 1997 study and show a worrying pattern, say the study's authors, led by Dr. Frank Biro of Cincinnati Children's Hospital Medical Center. Girls who hit puberty earlier are more likely to engage in risky behavior, Biro's team notes, and might be at a higher risk for breast cancer, than their peers who develop later.
"This could represent a real trend," Dr. Joyce Lee, a pediatric endocrinologist at the University of Michigan who was not involved with the new research, told Reuters Health.
Doctors are unsure of what could be causing girls to develop at a younger age, but rising obesity rates may be to blame, they say.
Female hormones are stored in fat. If girls are fatter then it would make sense this would be a reason for earlier puberty. Thin girls that exercise a lot may not have periods.
Answer by Gailll at 1:12 PM on Aug. 9, 2010