LOS ANGELES – Epidemic obesity rates are the “prime driver” in the U.S. trend toward earlier and earlier breast development in young girls, according to new research.
In a paper published Monday in the journal Pediatrics, researchers found that the average age of thelarche, or onset of breast development, was earlier than previously recorded for white girls, and that a high body mass index, or BMI, was a strong indicator of early puberty.
Although the study’s authors said it remained unclear whether early breast development led to early onset of menstruation, they said the trend toward earlier sexual development raised numerous clinical issues.
“Girls with earlier maturation are at risk for lower self-esteem and higher rates of depression,” wrote Dr. Frank Biro, lead study author and director of adolescent medicine research at Cincinnati Children’s Hospital.
“They are more likely to be influenced by older peers and more deviant peers, and initiate intercourse, substance abuse and other norm-breaking behaviors at younger ages,” Biro and his colleagues wrote.
The authors noted also that early maturation was associated with increased risk of breast, ovarian and endometrial cancer.
Researchers tracked the development of more than 1,200 girls in San Francisco, New York and Cincinnati. The girls were enrolled in the study when they were between the ages of 6 and 8, and were examined periodically from 2004 to 2011.