Why are our lady fluids so often depicted as blue?

Here's an interesting fact about women — none of our bodily fluids have ever resembled Windex. Not our periods, not our pee, not our amniotic fluid, not our saliva, none of it. It seemed for a moment there that this information had begun to take root into the public consciousness. But while a new study on female sexuality has brought new insights into a unique orgasmic phenomenon, it has also brought back a reminder of a familiar trope from the maxi pads ads of your youth — blue lady liquid.

A 2022 report out of Japan and published in the International Journal of Urology on the "Enhanced visualization of female squirting" sought to answer elusive question surrounding the phenomenon — what exactly people who squirt are squirting. In order to identify the source of the fluid, "A urethral catheter was inserted before sexual stimulation and the bladder was emptied. Then, a mixture of indigo carmine (10 ml) and saline (40 ml) was injected into the bladder." When the subjects were then sexually stimulated to the point of squirting, they squirted blue, confirming that most, if not all, of their fluid was urine. "This is the first report," the authors wrote, "in which visualization of squirting was enhanced."

Enhanced like an Yves Klein painting. Like a Delft tile. Like a Smurf. Blue.

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The use of dye as a means of visualization is commonplace in routine medical diagnostics like CT scans or X-rays. And indigo carmine in particular is a common agent in tests involving the kidneys and bladder. If you're hydrating, your pee should be pretty clear, which is good for your health but challenging for informational purposes. A vibrant blue, in contrast, says, "Look at me!" I have watched the video from that International Journal of Urology report and let's just say that the evidence is impossible to miss. It's like your favorite colored Paas Easter egg dye in a context you never imagined.

Yet that same shade has also long been synonymous with a kind of delicate discretion around other female discharge. For decades, if an advertiser wanted to explain the comfort and absorbency of a tampon or, more likely, a pad, they'd do so with a tranquil pour of swimming pool blue liquid.

Menstruation has long been framed in terms of managing it with the greatest possible degree of obfuscation. The earliest modern maxi pads were marketed with "silent purchase coupons" so ladies didn't have endure the shame of uttering a word. For thirty years, the Modess brand ran on an enigmatic yet glamorous campaign of "Modess… because." Tampons ads only started appearing on television in the mid 1970's, and it took a few more years for a young Courtney Cox to become one of the first people ever to say the word "period" on TV. (Just this week, Cox cheekily posted a menopause-themed riff on her iconic Tampax ad on her Instagram.)

All of this is to say that it has taken a long time for the mere fact of female emissions to be acknowledged at all. And somewhere along the way, blue liquid entered the chat — and stayed there. As design lecturer Jane Connory explained to Australian Broadcast News in 2021, blue is regarded as "fresh [and] clean," distinct "from red and the reality of blood." It was precisely because it's an unmistakably inhuman color that it was acceptable for advertisers. 

"Always Ultra is much better at holding wetness inside," purrs a woman in a television ad from the eighties, as test tubes pour blue liquid on pads. Two decades later, "The Always extra absorbent layer helps lock wetness, even in the middle!" a strikingly similar ad involving blue fluids and, this time, eyedroppers, explains. My favorite Always ad from the nineties includes an animation of a single, elegantly falling blue drop.

Over the past several years, the blue tide has, however, been turning. A groundbreaking 2010 Kotex ad poked fun at the stereotype, with a down to earth looking girl saying, "Ads on TV are so helpful, because they use that blue liquid. And I'm like, 'Oh, that's what's supposed to happen.'" A 2012 ad from the UK company Bodyform similarly mocked the convention, with a witty "apology" revealing "the truth" of menstruation from a woman sipping from a glass of bright blue water.

Yet blue dies hard. When the period care company Cora started using red liquid in its ads in 2018, they were flagged and initially removed on Facebook and Instagram. The color red only started showing up on Australian period product television ads in 2019. When they did, a vividly scarlet hued initial campaign from the company Libra prompted hundreds of complaints, calling the imagery "distasteful" and "unnecessary," to the nation's Ad Standards department. In 2020, Kotex unleashed a new advertisement featuring a deep red fluid falling as if from the heavens above upon a waiting, "ultra thin" pad. The Indian period product company Whisper just started employing red in its advertising in 2021. Even Always has for the past few years embraced red, now poured from a tiny cup.

But the taboos around female fluids persist. Just two years ago, Tampax was boasting — to hoots on social media — of its Pearl Compak tampons that "open silently for full discretion." The brand's Radiant line, meanwhile, "features our quietest, resealable wrapper to make changing your tampon quiet, easy, and discreet." Our fluids may today be less blue, but dammit, they're still so troublingly noisy.

The Japanese squirting visualization research was surely not an intentional nod to our globally and persistent  squeamishness around the normal and natural reality of our bodily fluids. It represents the consistent application of a dye commonly used for urinary tests. But it also inevitably evokes an image long held, that our functions are somehow overwhelming and discomfiting, that they are somehow rendered more wholesome in the hues of laundry detergent and toilet bowl cleanser.