Early puberty in girls has been found to have a negative effect on children's health, increasing the risk of mood disorders, substance abuse, adolescent pregnancy and cancers of the reproductive system. Researchers at the University of Arizona and the University of Wisconsin, Madison, followed 227 pre-school children over a number of years to see which factors led to girls going through puberty earlier. They found that children living in families with greater parental supportiveness (from both mothers and fathers), less marital conflict and less paternal depression went through puberty later than other children. Those whose mothers also started puberty later, who were from better-off families, whose mothers were more supportive of them in pre-school and who were lighter in early childhood also developed later than other children.
You can find out more about this research at