When we were at school, it used to be a bit of a joke that we’d skip PE lessons because we had our period.

It was an excuse few teachers wanted to argue with, after all.

But, when you think about how many girls truly dread getting unchanged and physically active in a school setting, it’s no laughing matter.

Especially when you consider that these feelings of shame and humiliation have a trickle-down effect on the representation of women in sport more generally.

Nearly half of women have used periods as a reason to skip PE classes at school, according to a new study by Betty for Schools, an initiative that encourages young people to talk freely about menstruation.

The findings come as the UK marks Women’s Sports Week, a national awareness campaign to raise the profile of women in sport.

Of the 46% in the study who said they’d avoided a PE class because of their period, more than a third (39%) said the fear of leaking was their biggest reason, while the second largest reason (24%) was a worry that their sanitary pads would be visible to others or slip out during exercise.

A massive 63% of the women surveyed said they “dreaded” PE lessons if they had their periods.

The questionnaire was completed by 2,000 adult women recalling their experience of periods and PE classes at school.

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Most of those questioned (68%) agreed that if girls received better education about periods and the way menstruation impacts the body, they would be more comfortable taking part in sports.

And a massive 73% said that period education should emphasise the host of benefits that exercising can bring to girls on their periods, including reduced bloating and pain relief.

The problem is bigger than just a school issue. Nearly 60% of the women surveyed felt that avoiding sports during their teen years negatively impacted their perception of physical activity as they grew older, too.

Just 31.9% of adult women take part in sports at least once a week, compared to 40.5% of women, figures from Sport England show.

Campaigns such as This Girl Can aim to redress this balance, as they investigate the barriers and triggers to getting women moving, “regardless of shape, size and ability”.

Their research indicates that fear of judgement lies at the heart of women’s reluctance to get active, and part of this surely stems from so-called “period shame” at school.

This gender divide impacts the professional world too. Funding is still a big problem when it comes to gender equality, with the profile and pay of women’s sports still massively out-sized by men’s sports.

However, progress is being made in some areas.

A total of 83% of sports now reward men and women equally, according to a BBC Sport study out this week.

Of course, while exercise can soothe period pain, we should also feel free to comfortably and honestly discuss its negative effects.

At the Rio Olympics last year, Chinese Olympic swimmer Fu Yuanhui bust open this particular taboo on a world stage, by talking openly about how her period affected her performance.

Read more: Family celebrates girl’s first period in a very unique – and badass – way

Crouched on the ground holding her stomach after the 4 x 100-metre medley relay – in which her team came fourth – the swimmer told reporters:

“I feel I didn't swim well today. I let my teammates down.

“Because my period came yesterday, I'm feeling a bit weak, but this is not an excuse.”

The point is, she opened up conversation about what is often – even now in the 21^st Century – a very closed subject.

Team GB’s Olympic Gold hockey medallist Sam Quek is one athlete who has put her weight firmly behind the Betty for School’s campaign to shatter period taboos.

The Olympic champion took over Betty for School’s Instagram feed this week, to highlight the normality of periods. She demonstrated how girls and women can integrate exercise into their daily lives – even while menstruating. 

“We women are one of a kind,” she says. “If we want to get out there, if we want to get fit, if we want to be the best we can be – don't let anyone or anything ever stop you. Whether that is because you’re on your time of the month and feeling rubbish, or whether someone tells you you’re not good enough.”

We 100% agree.

See more about the Betty for School programme right here.

Images: iStock, Rex, Instagram