When actress and activist Sophia Bush learned that nearly one in five girls in the United States are estimated to have missed school due to a lack of period products, she was aghast.

"So many girls lose out on their opportunity to get educated because they live in period poverty," Bush told " Good Morning America." "What period poverty means is that you don't have access to the sanitary items that you need to manage your cycle."

At least 500 million women and girls globally lack facilities for managing their periods, according to a 2015 report from the World Health Organization and UNICEF.

That's heartbreaking that young women are losing out on their opportunity for education.
PHOTO: Always joined forces with actress Sophia Bush for a campaign to help end period poverty in the U.S.
Michael Simon
Always joined forces with actress Sophia Bush for a campaign to help end period poverty in the U.S.

Bush is partnering with Always to raise awareness about the reality of period products and the impact it has on women.

"So they don't go to school because they can't," Bush said. "They can't sit in their clothes through a school day if they don't have access to sanitary products and that's heartbreaking that young women are losing out on their opportunity for education, that every month they're missing days of school because they can't afford to leave the house."

"As a long time education access advocate, I truly believe nothing should stand in the way of a girl and her education. Nothing! Certainly not her period," Bush wrote in an Instagram post.

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When I think about #BackToSchool season, and all of the joy that school brought to me (this serious tween face aside) I think about possibility and potential. To learn that nearly 1 in 5 girls in the United States has her potential cut short and winds up missing school because of period poverty? I was aghast. 88,000 girls in the Los Angeles area alone have missed school because their family couldn’t afford period protection. Period poverty affects girls EVERYWHERE. And I believe that we have to bring awareness to this disparity so we can actively start solving this education crisis. That’s why I’m partnering with @Always_brand as they continue their mission to #EndPeriodPoverty and keep girls in school. Last year they donated 20 million products to girls in need through @FeedingAmerica, and this year we want to donate millions more! As a long time education access advocate, I truly believe nothing should stand in the way of a girl and her education. Nothing! Certainly not her period. During the month of September, you can spark product donations and support local period heroes who are already making a difference. Join us! Head to always.com/endperiodpoverty to learn more. #ad #AlwaysPartner #EducationIsEverything

A post shared by Sophia Bush (@sophiabush) on Sep 10, 2019 at 8:43pm PDT

"So many people are shocked when they learn about period poverty being so prevalent here," Bush said. "I think that we often assume that something like that couldn't happen in the U.S."

It is estimated that 143,000 girls in the New York City area and 88,000 in the Los Angeles area have missed school because of period poverty, according to a 2019 study by Always.

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"When a family has to choose between rent money or food money, that means that they don't have the financial resources to buy packages of period products every month," Bush said. "And it's a devastating reality for a lot of people who just are not getting the support that they need in this country."