Young girls on their periods are taking time off from school because they can't afford to buy sanitary products, such as tampons and pads.
The discovery was made by staff at the charity Freedom4Girls, which provides sanitary products to women in Kenya, after a school in Leeds contacted them about the issue.
"We had an idea that there was something happening in schools. It's linked to poverty - 25,000 visits to food banks just in Leeds last year,” she said.
"We need to give these girls their dignity back."
Two teenage girls from Leeds also spoke to the BBC to describe how they use makeshift sanitary protection when they are on their period, because tampons and pads are simply unaffordable to them.
"I wrapped a sock around my underwear just to stop the bleeding, because I didn't want to get shouted at,” said one, whose mother is a single parent with five children and a very limited budget.
“I wrapped a whole tissue roll around my underwear, just to keep my underwear dry until I got home,” she continued. “I once Sellotaped tissue to my underwear. I didn't know what else to do.”
The other teen admitted she took a few days off school when she got her period because she didn’t understand what was happening to her body and she was scared.
"That made my attendance really low and I was getting in trouble,” she said.
“One day the teachers came to my house and asked why I'm not at school and they actually took me to school. I thought it was only happening to me... so I was scared and I wanted to stay at home."
Unfortunately it seems likely the issue of teenagers and their parents being unable to afford tampons and pads is UK-wide.
"If you've got no food, you've got no money for sanitary protection,” Leslie said simply, adding that much more research was needed to establish the size of the problem across the country.
Although it’s clear more needs to be done, there are a number of charities and food banks that help provide teens with the products they need when they’re on their periods. For more information, or to volunteer or donate, head to The Trussell Trust, The Homesless Period or The Bloody Good Period.