Early puberty is often associated with advanced skeletal age, meaning that a 6 year old girl might have the bone structure of an 8 or 9 year old.

青春期早发通常伴随着增加的骨骼年纪，例如一个6岁的女孩可能拥有一个8到9岁女孩的骨骼结构。

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Boys are more likely than girls to have an underlying physical cause for early puberty, but boys in this study were most likely free of any physical conditions that might explain the results, said lead author Marcia Herman-Giddens, a researcher at the University of North Carolina in Chapel Hill.

FORBES: Study Shows that Early Puberty is Now Affecting Boys, Just Like Girls