Scientists believe that as humans evolved, leptin assured that a girl who became fertile had enough fat to sustain a pregnancy. Compared to girls 20 years ago, those in Herman-Giddens' study were taller and heavier. In white girls, it seems to explain a whole lot of early puberty. With black girls, it's more complicated, perhaps a combination of genetic and environmental factors. Whatever is going on, the implications are significant.
Puberty triggers a growth spurt.
In such rare cases, the new guidelines say, hormone treatment to delay puberty may be warranted. Early bloomers are also prime candidates for teasing from peers, and sexual abuse by older adolescents. If a child and her family aren't coping well, hormone treatment may be considered, the guidelines say. And that brings up The Talk. We're seeing girls beginning physical development earlier.