Puberty Starting for Girls as Young as 6

The first signs of puberty are appearing earlier and earlier in American girls, reports the Los Angeles Times. Early breast development is becoming so common that some experts are suggesting that the age at which it is considered abnormal be shifted down to 6 years of age for African-American girls and 7 for Caucasians. Later signs of puberty, pubic hair and menstruation, are appearing at intervals further apart, puzzling pediatricians.

Records show that girls reached puberty four years sooner in 1950 than they did in 1850, a change experts credit to improvements in health. "We're healthier and we weigh more," a doctor explained. "In some ways, puberty is a luxury." Doctors are concerned, however, that the puberty is now getting earlier because of negative factors like obesity and environmental toxins. (More puberty stories.)