Girls in the United States have been getting their periods at younger ages over the last fifty years, with additional variation among races, according to a new study. The study published in the JAMA ...

Menstruation is a natural biological process experienced by nearly half the global population. Yet, for many girls, the first period arrives as a surprise—often misunderstood, feared, or even ...

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 ...

Add Yahoo as a preferred source to see more of our stories on Google. A new study of 71,341 women supports the growing concern that the age at which girls start menstruating is getting younger, and ...

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It doesn't have to be awkward.

Around half of teenage girls experience moderate to severe period pain. The mechanical force of the uterus contracting and inflammatory chemicals such as prostaglandins contribute to this pain.

SDI Productions/Getty Images / E+ 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 ...