Training bras, tampons, and too many tears—the transition from girlhood to womanhood has always been rocky.
But new research suggests that for girls experiencing puberty on the earlier end of the spectrum, the transition may be even harder. A recent study published in the journal Pediatrics has found early puberty in girls raises the risk of depression. With puberty now coming earlier for many girls, these findings could affect more girls than ever before.
The study focused on a group of nearly 8,400 children in Hong Kong born in April and May of 1997. The researchers had access to records detailing the physical maturity of the children using the Tanner stages, a standardized index used to measure sexual maturation that spans from before puberty to full physical maturity. On average, most girls begin puberty between the ages 10-14.
In this study, researchers examined the relationship between the age that children moved from pre-puberty to the physical beginnings of puberty and the likelihood of depression in those children when they reached the ages of 12–15.
Here’s Perri Klass, reporting for The New York Times:
“What we found was the girls who had earlier breast development had a higher risk of depressive symptoms, or more depressive symptoms,” said Dr. C. Mary Schooling, an epidemiologist who is a professor at the City University of New York School of Public Health, and was the senior author on the study. “We didn’t see the same thing for boys.” Earlier onset of breast development in girls was associated with a higher risk of depression in early adolescence even after controlling for many other factors, including socioeconomic status, weight or parents’ marital status.
Other studies, including in the United States, have shown this same pattern, with girls who begin developing earlier than their peers vulnerable to depression in adolescence. Some studies have found this in boys, though it’s not as clear. But there is concern that girls whose development starts earlier than their peers are at risk in a number of ways, and across different cultural backgrounds.
Before puberty, depression occurs at roughly the same rate for both boys and girls, but midway through puberty, girls are two and a half times more likely to be depressed, according to Jane Mendle, a clinical psychologist at Cornell University.
Schooling pointed out that in their study, hormonal changes controlled by estrogens, like early breast development, were linked with higher rates of depression, whereas hormonal changes controlled by androgens, such as pubic hair development, were not.
That would strongly suggest that estrogen plays some kind of role in adolescent depression. However, estrogen has already been ruled out as a driver of depression in earlier research. It’s possible that social factors could offer an explanation, Schooling said.
Dr. Mendle speculates that fitting in amongst peers remains a core issue in those that begin puberty early. Developing early changes the way people treat you—from your friends to the adults in your life to complete strangers. Girls who look different from their peers have difficulty maintaining friendships, and they’re more likely to be harassed by their peers, said Mendle.
As well as social challenges, girls who go through puberty earlier have to confront these physical changes with much less emotional maturity and cognitive development than their peers. These two factors combined, says Mendle, could create a situation where depression becomes more likely—but further research is needed to know for sure.