For a couple decades now, scientists and parents alike have been noticing that some girls are hitting puberty earlier and earlier, some as young as six years old. For a while, it was feared that girls starting puberty around age 9 might become the new norm, but fortunately that doesn’t seem to be the case.
And this is part of a trend?
According to Weil’s report — “Puberty before age 10: A new ‘normal’?” — Ainsley is part of a growing tide of young girls forced to confront the mounting pressures of puberty at an increasingly young age. A large study published in the journal Pediatrics found that 10 percent of white girls, 23 percent of black girls, 15 percent of Hispanic girls, and 2 percent of Asian girls start growing breasts by the age of 7. But that earlier breast development hasn’t generally been accompanied by an early first period.
Why are some girls developing earlier?
Researchers are still trying to figure that out. Typically, “girls who go through puberty early fall into two camps,” says Weil: “Girls with diagnosable disorders like central precocious puberty, and girls who simply develop on the early side of the normal curve.” Young “girls who are overweight are more likely to enter puberty early than thinner girls,” says Weil. And some environmental chemicals, like the flame retardant PBB, can alter a young girl’s timing by changing her hormone levels. Stress “can disrupt puberty timing as well.”
So while the jury is still out, some of it is just natural variation, while some of it seems to be reactions to modern environmental chemicals and possibly low levels of hormones in food. If you’ve been keeping up with this scientific inquiry, you know that this does seem to be almost all girls who seem to be slowly trending towards puberty at younger ages, not boys.