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 more girls are beginning menstruation before the age of 9, which ...

Black children of low socioeconomic status are starting their periods earlier than the average age, and it takes more time for their menstrual cycles to become regular, according to a new report. In a ...

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 ...