Stress Linked to Girls' Early Puberty

Nov. 15, 2007 -- Findings from a newly published study support the idea that family conflict can influence the timing of puberty in girls.

Bruce Ellis, PhD, of the University of Arizona, and Marilyn Essex, PhD, of the University of Wisconsin, followed children from preschool to middle childhood. They also conducted interviews with the children's parents to assess family stresses, including economic difficulty, marital problems, parental depression, and parenting style.

They found that girls living in families with greater parental support and less marital conflict experienced their first hormonal changes later than other children. Marital conflict, poor parent support, and depression among fathers, but not mothers, was associated with earlier puberty.

The results suggest that even modest family conflict or stress may influence a young girl's sexual development, Essex tells WebMD.

"These were the normal stresses of growing up, not serious abuses," she says.

The study is published in the November/December issue of the journal Child Development.

Early Puberty and Evolution

The new research adds support to the theory that earlier sexual development among girls in response to family and other stress may have an evolutionary basis.

The thinking is that children who grow up under stressful, and potentially dangerous, conditions have a better chance of having their genes survive if they reach sexual maturity earlier.

But in modern society, early puberty among girls is a risk factor for many health problems, including depression and other mood disorders, substance abuse, early pregnancy, STDs, and cancers of the reproductive system.

"From a public health standpoint, stemming the high incidence of early puberty among girls would be beneficial," child development researcher Jean Brooks-Gunn, PhD, tells WebMD.

Her own research at New York's Columbia University shows that girls who reach sexual maturity early are at increased risk for psychological problems, aggression, and being abused by a partner.

Genes, Environment, and Puberty

The most important factor for determining when a girl will reach puberty is the timing of her mother's first menstruation.

But it is increasingly clear that factors other than genes are at play in the sexual maturation of girls.

There is growing evidence, for example, that being overweight early in life is associated with early puberty.

Brooks-Gunn says the new findings on family stress point to the complexity of the timing of sexual maturity in girls.

"What is it about conflict in the house or having a father who is depressed that translates into earlier puberty?" she asks. "That is the interesting question to me. There are many possible answers, but we don't really understand this yet."