Girls in the U.S. are getting their first menstrual period about 6 months earlier on average than they did in the 1950s and '60s. And the number of girls starting their period before age nine has ...

The study found that the percentage of girls getting their period before the age of 11 grew from 8.6% to 15.5%, and those who began menstruation before age nine more than doubled.

Girls in the U.S. are getting their first period earlier than in decades past. Researchers say there are multiple factors causing early puberty, including obesity and environmental pollutants.

Girls have been getting their periods earlier and earlier for more than half a century. And as early onset increased, it has taken longer and longer for menstrual cycles to become regular.

Girls in the U.S. are getting their first menstrual period about 6 months earlier on average than they did in the 1950s and ‘60s. And the number of girls starting their period before age nine ...

A new study, published Wednesday, found that girls are starting their menstrual cycles earlier now than in previous decades.The trend is more pronounced for girls from minority groups and those ...

Girls in the U.S. are getting their first menstrual period about 6 months earlier on average than they did in the 1950s and '60s. And the number of girls starting their period before age nine has ...