Girls Overweight at Young Age May Enter Puberty Earlier

There may be an important link between two prevalent U.S. trends. A new study suggests that the increasing rate of childhood obesity (which has more than doubled since the 1970s) may be contributing to the increasing rate of early puberty in girls. And the effects may start long before girls approach their preteens. In fact, researchers found that girls who have "increased body fatness" as early as the preschool years are more likely to start going through puberty sooner.

Researchers followed the development of more than 350 girls from age 3 until age 12. The study found that girls tended to enter puberty earlier when they had higher body mass index (BMI) scores at age 3 and a "higher rate of change" in BMI between age 3 and the first grade.

The odds of entering puberty earlier went up by 44% for each 1-point increase in BMI score at 3 years old. The study also found that girls started going through puberty earlier if they were non-white (mostly African American) or had a mother who had also physically matured early.

By the fourth grade, 30% of the girls were either at risk for being overweight or overweight, and 168 — or nearly half — were considered to be "in puberty."

The study noted that early puberty has been associated with other health issues, including:

• mental health and behavioral problems
• difficulty functioning socially
• using alcohol earlier
• earlier sexual intercourse
• teen pregnancy
• greater likelihood of being obese and having reproductive cancers as an adult

The researchers say more studies need to be done to figure out why obesity at a young age might lead to early puberty and if controlling a young girl's weight might lower the risk of early puberty.