Absence of Biological Father is Linked to Early Puberty, Study Says
Girls who don't live with their biological fathers are more likely to hit puberty at an early age -- but only in households with higher incomes, a new study says.
The findings are based on three annual surveys of 444 girls between the ages of 6 and 8 in which researchers looked for the signs of puberty that emerge before a girl has her first period. The researchers, from University of California, Berkeley's School of Public Health, also asked questions about the people living in the girls' homes and their relationships to them.
Of the girls studied, 80 didn't live with their biological fathers at the time of the first survey, according to an article to be published in the Journal of Adolescent Health. The researchers found a link between father absence and early breast development in girls who lived in households with annual incomes of $50,000 or more.
The absence of a father also predicted earlier development of pubic hair, but only for girls in African American families in the $50,000-plus income bracket, the article says.
The findings were consistent even after the girls' weight -- often considered a factor in early puberty -- was taken into account. Early puberty has been tied to breast and other reproductive cancers later in life.
"The results from our study suggest that familial and contextual factors -- independent of body mass index -- have an important effect on girls' pubertal timing," Julianna Deardorff, the study's lead author and assistant professor of maternal and child health at UC Berkeley, says in a statement.
The reasons for the link between paternal absence and early puberty are not clear, the authors write, nor why income and race are factors.
"It's possible that in lower income families, it is more normative to rely upon a strong network of alternative caregivers," Deardorff says in the statement. "A more controversial hypothesis is that higher income families without fathers are more likely to have a single mother who works long hours and is not as available for caregiving. Recent studies have suggested that weak maternal bonding is a risk factor for early puberty."
Start by teaching him that it is safe to do so.