Earlier Puberty in Girls Noted

In the long-running discussions over sex education, one fundamental question has to do with the appropriate age for children to learn various things. When is it appropriate to learn the names of body parts? When should intercourse and reproduction be explained to them? When should they learn about the risks of various sexual behaviors, including oral and anal sex? The trick is preserving the innocence of childhood while providing information that young people need as they become physically mature and sexually active. Their bodies are changing and their emotions are changing as they approach and pass through puberty, and the likelihood increases that they will need more precise and thorough information about adult things.

The educational question hinges on timing information to students' physical, cognitive, and emotional growth. Assumptions are made about the maturation process, and that process itself is changing. Kids are growing up faster now.

The New York Times:

A new study finds that girls are more likely today than in the past to start developing breasts by age 7 or 8.

The research is just the latest in a flood of reports over the last decade that have led to concern and heated debate about whether girls are reaching puberty earlier, and why it might be happening.

Increased rates of obesity are thought to play a major role, because body fat can produce sex hormones. Some researchers also suspect that environmental chemicals that mimic the effects of estrogen may be speeding up the clock on puberty, but that idea is unproved. First Signs of Puberty Seen in Younger Girls

We don't have access to the study itself, but Politics Daily summarizes the results:

The study, led by a team of researchers at the Cincinnati Children's Hospital, found that at the age of 7, 23.4 percent of African- American girls, 14.9 percent of Hispanics and 10.4 percent of white girls had developed breasts. By 8, those proportions had risen to 42.9 percent, 30.9 percent and 18.3 percent, respectively. The percentages for blacks and whites were even higher than those found by a 1997 study that was one of the first to suggest that puberty was occurring earlier in girls.

While the causes of this trend are unknown, one chief culprit is thought to be obesity. Body fat produces estrogen, which in turn triggers breast development and menstruation. Another possibility are endocrine-disrupting chemicals in the environment -- such as bisphenol-A (BPA) -- which is found in many hard plastic products, including water bottles and baby bottles. Early Puberty in Girls: What Are the Social Consequences?

But one of the researchers cautions that the data in this study are not sufficient to support the conclusion that puberty is coming earlier in general. ABC News:

One of the study's authors told ABC News' Senior Health and Medical Editor Dr. Richard Besser, however, that determining early puberty was not the focus of the research.

"I don't think from this study we can say the age is going down in the world at large," said Mary Wolff, who is a professor of community and preventive medicine at Mount Sinai School of Medicine. "This study was not designed to look at if puberty was happening early or not."

The authors point out that the study does not use a nationally representative sample of subjects, and does not look at development over time to account for environmental exposure, dietary differences or other factors related to race and ethnicity. Additionally, some subjects were selected because they had existing risks for early puberty.

Another important element missing from this study is information about the onset of menstruation, which could indicate whether puberty has actually started.

"It's going to take a lot of follow-up to say whether this is really puberty," said Dr. Abby Hollander, associate professor of pediatrics at Washington University School of Medicine in St. Louis. "Within five years, we should be able to say whether the average age girls get their periods is earlier." Is Puberty in Girls Coming Too Soon?

This study did not attempt to determine the age of onset of puberty in the general population, but it does add to a body of literature that indicates that that age has been dropping steadily. The two likely culprits are obesity and endocrine disruptors in the environment that mimic the effects of estrogen.

Educators should consider this change in our world as they develop curricula to inform young people about their sexuality. It may seem shocking to teach elementary school children the details of sexual intercourse and the risks of sexual behaviors and how to avoid them, but it may be necessary if students are reaching physical adulthood in those grades.