Hunched over a hot water bottle. Bent over in pain. Curled up in the fetal position. This is how menstruating women are portrayed in 91 percent of stock imagery and image search engine results, according to a new analysis of online period-related content.

Period subscription service Pink Parcel conducted an analysis of period-related content from 100 popular websites, including Google, Bing, and the UK's National Health Service (NHS) website. The findings — emailed to Mashable— revealed that nine in 10 images depicting menstruation showed women looking "weak, upset, or vulnerable." Stock image sites, search engines, and health advice sites found to be the worst offending sources.

According to the analysis, 63 percent of images showed women clutching their stomachs, 40 percent featured women "in crippling pain," and 52 percent of images portrayed women lying down. In contrast, a mere 9 percent of the images analysed featured women at work or playing sports.

These images of menstruating women looking helpless and incapacitated are everywhere. But the knowledge that they aren't reflective of women's experiences of menstruation is, unfortunately, not as ubiquitous. These images aren't just propagating false information, they're reinforcing an age-old stigma that women on their period are weak and vulnerable.

A cursory image search seems to confirm the findings. Type in "woman period" to Google Images, Getty, or Shutterstock, and you'll be bombarded by images of women clutching their abdomens, wincing in agony as they press hot water bottles to their bodies.

These images tell a story of women weakened and incapacitated by their periods. That's not to say that menstruation isn't painful, and some women experience more pain than others during menstruation. Conditions like endometriosis, a condition that affects 10 percent of women in the UK, can lead to severely painful and debilitating periods. But these online representations simply do not tally up with most women's experiences of having periods.

More than half (56 percent) of women say images used to depict periods are "not relevant to them," according to Pink Parcel's survey of British adult women. And, 40 percent of women surveyed said negative online content is a "key cause of feeling period shame."

Mashablereached out to Getty Images to ask about its representations of menstruation in stock images. Craig Peters, COO and executive vice president at Getty Images, said in a statement that "some images may not reflect contemporary views," but that Getty doesn't believe it should "limit customer choice, as the customer alone understands the context and objective of their message."

Peters added that he would encourage customers to "think outside general search terms" when searching for images.

"For example, 'menstruation' may bring up images that specifically speak to symptoms, however images of 'women playing sport,' ‘women at work,' 'women leaders,' etc. can and should also be used to tell the story," Peters added.

Stock images aren't the only sources of false information about periods. The persistent myth that women are less capable during their time of the month isn't just the subject of many a bad joke, it's also been perpetuated by outdated scientific research. Past research has claimed that women's cognitive functioning was affected by estrogen and progesterone, suggesting that women are less competent at certain times of the month. But a 2017 study finally put an end to this tired, age-old idea that women's periods make them incompetent.

While stock images are failing to to depict the reality of menstruation for the majority of women, there are other communities that are entirely overlooked in period-related stock imagery. Trans men and gender-nonconforming people also have periods, but their experiences of menstruation are notably absent in these images, and often left out of conversations about periods overall.

Trans teen Ethan Lopez penned an essay for Sex, Etc about just how problematic it is to portray menstruation as a female-only experience.

"I find it limiting when menstruation is regarded solely as a 'woman's experience,' like when people use phrases such as 'entering womanhood' when referring to menstruation and 'feminine hygiene products' when talking about tampons, pads, or menstrual cups," Lopez wrote. "The idea is that men don't have periods. That’s untrue."

So, how do people respond to seeing these stereotypical period-related images? When asked to look at a selection of images portraying women on their period, 31 percent of British people perceived the women as "fragile," per Pink Parcel's analysis. And 12 percent of those surveyed stated that periods are "something to be ashamed of."

Recent research by period underwear manufacturer Thinx found that 60 percent of women feel embarrassed simply for having their period, and around three-quarters hide their tampons and sanitary pads from sight because they don't want people to know they're menstruating. And, according to Pink Parcel's research, more than a third of women still see periods as "a taboo subject," and 50 percent never speak to their partners about their period.

But when the vast majority of online images portray women on their period as weak and incapacitated, is it any wonder women are reluctant to reveal that they're menstruating?

"It is little surprise period shame is so prevalent when demeaning images are continually perpetuated by the media and society," Pink Parcel marketing manager Alycia Haynes said in a statement.

"Our research has proven that this consistent stream of dramatised, unrealistic images is leaving those who experience periods feeling ashamed, embarrassed and reluctant to talk about them," Haynes continued.

Pink Parcel has launched a line of clothing emblazoned with "period positive slogans" as part of its I'm On campaign, in an effort to challenge "negative perceptions of periods."

But it'll take a lot more than a slogan tee to challenge the long-standing stigmas that surround the topic of menstruation.

It's time stock image sites took a long, hard look at the period-related images they produce and sell. The world needs more images of women looking capable, competent, and content during their period — because that's the reality of menstruation.