I was a pretty late bloomer. At the time, I felt kind of weird about it, like I was missing out on something. Now I know. The earlier you bloom, the longer you have to deal with all that... girl stuff.
So that's what makes me (and probably you) cringe to hear in the news "Puberty Strikes 7-Year-Old Girls." A study of girls in areas of NYC, Cincinnati, and San Francisco showed "a surprisingly large bump in the number of girls going through puberty between the ages of 7 and 8." That means first or second grade! I remember early bloomers in my generation were girls who got their period in fifth grade. This study shows that 10 to 25 percent of girls, depending on their race, are developing breasts at age 7 to 8. Girls that young don't seem emotionally equipped to handle the hormones and body changes, much less the attention they'll get from boys (some who won't mature for a decade later).
The real cause of this shift toward earlier puberty is unknown, but experts suspect it has to do with rising obesity rates (having a certain amount of body fat can trigger puberty hormones) and increased exposure to estrogen in the environment (in plastics, chemicals, and foods – creepy).
The study's lead author says "living green," eating well, and exercising may help put off puberty.
Here are some resources to help (and here's hoping that your girl doesn't get her 'girls' until her teens):