Over the past several years, a patchwork of tech and personal care companies have plunged millions of dollars into a race to control the baby product of the future: smartphone-enabled diapers.

Leading the charge is Huggies, which has rallied an obscure invention — a Bluetooth sensor that texts parents about their babies’ bowel movements — into the centerpiece of its “smart diaper” line Monit x Huggies. After launching smart diapers in Korea last October, the company appears set to bring the product to the US as soon as this summer. The technology is reminiscent of a similar feature that Huggies considered releasing in 2013, then scrapped: TweetPee, a diaper sensor that slides into a parent’s DMs when their baby needs to be changed.

Although Huggies would be the first major company to bring its product to market in the US, it is only one player in the sprawling diaper-tech war. The health care company Pixie Scientific has been testing diapers that track infant urinary health since 2013, while Google’s parent company Alphabet submitted a patent last year for a carbon fiber-laced diaper that alerts parents about a shift in diaper equilibrium, including by distinguishing between poop and pee. The Chinese personal care giant Hunan Cosom lists smart diapers among its products, as does the Chinese tech company Opro9.

Even Huggies’ main rival, Pampers, is working to revamp its product: Since 2014, Pampers has tested individualized diapers that fit to each baby’s unique “pee points” to maximize urine absorbency.

That long march toward making smart diapers happen has been driven more by fears of slipping market shares than by any kind of real demand from consumers. The furious pace of innovation belies the fact that the US diaper market is in trouble. As the birthrate declines for the seventh year in a row, there are fewer and fewer new parents to buy diapers, and almost all major diaper brands have taken hits. After Kimberly-Clark, which manufactures Huggies, laid off 13 percent of its workers in January 2018, the CEO told investors, “You can’t encourage moms to use more diapers in a developed market where the babies aren’t being born in those markets.”

Last summer, to counter wilting sales, Pampers raised the price of its signature diaper by 4 percent. Huggies is making a bet different bet: By selling upscale diapers, it hopes to recoup the profits lost to a rapidly shrinking baby diaper market.

“The fact that the birthrates are quite low in the US has stirred a lot of interest in trying to get the consumer to spend more,” said Ali Dibadj, who tracks the personal products industry for the investment management group Sanford C. Bernstein. “The only way they can increase their business is to bring better products to the market. Their whole hope is to create products that the consumer base will pay more for.”

That puts Huggies squarely in line with other companies advocating seemingly unnecessary tech infusions into ordinary hygiene products on the bet that it will widen their profit margins. The brands behind the major US diapers have already flooded the market with “smart” toothbrushes, razors, and skin care wands, all of which they hope will entice wealthier consumers who can be convinced to drop the extra money.

Later this year, Procter & Gamble, which manufactures Pampers, is launching an AI toothbrush that claims to improve brushing. While typical electric toothbrushes cost around $30, P&G is planning to start its AI brush at $279, a massive price jump that foreshadows the future of the smart diaper. Kimberly-Clark, for its part, promised more “meaningful innovation” of its personal hygiene products, although the company already boasts everything from smart toilet paper to smart restrooms equipped with sensors that relay data about soap and toilet paper use.

“The fact that the birthrates are quite low in the US has stirred a lot of interest in trying to get the consumer to spend more”

Tony Park, who developed the Bluetooth sensor used in Huggies’ smart diapers, told Vox that Huggies was planning to roll out the diapers in the US and Mexico this August. A spokesperson for Kimberly-Clark responded that while the company was considering a US launch, “we have not made any final decisions at this time.”

Yet smart baby diapers feel like an inevitable fixture of America’s future, not least because smart diapers for older adults are already alive and thriving. “The smart concept has impacted many of their other businesses,” said Dibadj, referring to Kimberly-Clark and P&G. “They usually don’t spend money on research without actually trying to commercialize it.”

There is not a lot to a smart diaper — the removable Bluetooth sensor, which resembles an orange disk, can be attached to the outside of any regular diaper. That sensor syncs to a Huggies smartphone app, where it relays information about the temperature and air quality, and — in addition to individual alerts about baby poop or pee — tracks the overall frequency of a baby’s bowel movements and calculates the times of day the diaper tends to need changing. No more than five people can register as guardians on the app.

Park also noted that companies like Huggies could use his sensor to gather data on their customers. When they change diapers, parents are supposed to place the Bluetooth sensor on the floor and then reattach it to the new diaper. According to Park, the sensor counts each time parents switch diapers, offering Huggies a window into the number of diapers customers use each month or year. “We can track their buying record through the app,” he said.

The modern disposable diaper dates back to Marion Donovan, a former Vogue editor and a mother of two who, in the early 1940s, grew tired of the excruciating old system for pee management: a leaky strip of cloth that parents needed to wash frequently. The only alternative at the time, rubber baby pants, was also a bust — left for too long, it irritated her babies’ skin. So Donovan devised a simple alternative: a waterproof outer lining called a boater that enclosed absorbent paper, which could be thrown out with ease.

In 1949, Donovan’s new disposable diaper hit the high-end fashion circuit, debuting at Saks Fifth Avenue to a groundswell of success. Only in 1961, when Procter & Gamble launched Pampers, did Donovan’s disposable diaper reach the wider public.

Most babies already have an effective built-in alert system (crying), and the cost of a text alert is not worth it for many parents

In the subsequent decades, and especially after the 1978 launch of Huggies cemented it as the main competitor to Pampers, diapers have been the subject of a veritable innovation arms race: Diaper brands have poured billions of dollars into fine-tuning their products, to the point where diapers today are a multilayered marvel of scientific achievement.

P&G, for instance, boasts two separate diaper research and development centers in Cincinnati and Germany employing more than 250 researchers, who have filed 5,000 new diaper patents in total. They’ve turned obscure materials like “superabsorbent polymers” into commercial hits. The result is that modern diapers can do the miraculous: absorb urine within instants, all without making babies feel wet or compromising the light, fluffy texture that makes diapers wearable for newborns.

Diaper sensors that connect to smartphones are in some ways the natural progression of this tradition of invention. Companies that have exhausted the Marion Donovan-style diaper design see phone integration as the next best way to lure customers. Yet it’s not entirely clear who the target audience for tech-infused diapers even is. Diapers are a low-life-span purchase, meaning there is no great incentive for parents to invest in a particularly dynamic version.

Asked if he expects a lot of smart diapers customers to come out of the woodwork, Dibadj laughed. “I would not say it’s a big segment,” he said. While there are certainly some material benefits — instant alerts to a wet diaper can let parents focus on other tasks, for instance — most babies already have an effective built-in alert system (crying), and the cost of a text alert is not worth it for many parents. “I think you could find people who would want to buy such things, but I wouldn’t say it’s the top priority for consumers,” Dibadj said.

Park told Vox that the design is personal for him. Some babies, like his daughter, don’t cry when their diapers need changing, and figuring out when to switch diapers before a rash develops is a challenging guessing game. His target customers are millennial first-time parents who don’t have the time to constantly check diapers. “They are quite busy working two jobs,” he said. “They want to get involved in parenting, but they don’t have enough time to share with their baby. With our Monit device, they can get a notification whenever and wherever.”

“I think you could find people who would want to buy such things, but I wouldn’t say it’s the top priority for consumers”

But with the US price of a Monit Bluetooth sensor estimated at $249, according to Park, it’s not clear that millennial parents already struggling to make ends meet will drop so much cash on a diaper that texts.

All of this comes in an era when nearly one-third of parents cannot afford regular baby diapers — meaning the kind that doesn’t text you when your baby pees — and diaper affordability is becoming a priority among U.S. lawmakers. In March, Rep. Barbara Lee (D-CA) introduced the End Diaper Need Act, which would create a $100 million fund for distributing free diapers to low-income families — three years after the Obama administration outlined the need for a similar proposal.

“I would prefer that Huggies was going in the direction of affordable diapers instead of more expensive diapers,” said Kristin Rowe-Finkbeiner, president of the Seattle-based mother’s advocacy group MomsRising.

The problem of diaper unaffordability is entrenched. Although some diapers are cheaper than others, a supply of the average diaper costs around $1,000 per year, according to the Tampa Bay Times. Organizations like the National Diaper Bank Network have sprung up in order to offer free diapers to low-income families, but many advocates point to the need for more systemic fixes. The US is the only industrialized country that doesn’t guarantee paid leave to the parent of a newborn, for instance, which makes having a baby especially precarious.

“If you look at what’s happening with young families, the economic pressures are intense,” said Rowe-Finkbeiner. “A quarter of young families are living in poverty.”

For parents who work full time, not having access to diapers means further strain. Most child care centers require that parents drop off an adequate diaper supply along with their newborns, which means that the children of low-income parents are often forced to stay home.

To Rowe-Finkbeiner, these inequities are inextricable from the smart diaper discussion. She points out that the first country to receive the new Huggies smart diaper — Korea — already has paid parental leave laws. But in the US, with so many new families struggling to make ends meet, Rowe-Finkbeiner does not see the appeal of more gadget-friendly diapers.

“The pressure on families is really intense right now because we lack the basic support that many other countries take for granted,” she said.

In an era of such widespread inequality in who can afford to raise a kid and how, smart diapers seem like a play for the highest income bracket. But with the birthrate declining and baby care companies eager for ways to up their bottom line, diapers joining the ever-growing ranks of personal care products made “smart” might be inevitable.

Advocates like Rowe-Finkbeiner are not inherently opposed to diapers that text you about your baby’s pee and poop, either. She just has a few demands she’d like to see first, including a national system for paid family medical leave, increased access to child care for working parents who can’t afford it, and institutional support for new mothers. “And then maybe after that, we can get smart diapers,” she said.

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