New wearable, high-tech baby monitors raise questions about co-sleeping risks

New wearable, high-tech baby monitors raise questions about co-sleeping risks

The new generation of baby monitors hitting the market doesn’t just tell parents when their infants are crying. These high-tech devices can track a baby’s pulse and breathing, and are designed to alert parents if their little one rolls over, or hasn’t moved for 20 seconds.

The price tag for such close health supervision is hefty, with the devices costing between $130 and $550. But for those who can afford it, the expense feels insignificant compared to the horror parents hope they will help prevent: sudden infant death syndrome, commonly known as SIDS.

This may be a false hope. Top pediatricians warn that the physical and biological events leading to SIDS deaths remain poorly understood, and that none of these devices, which can be clipped onto a baby’s diaper or wrapped onto a foot like a sock, has been demonstrated to lower the risk of sudden sleep deaths.

And their use may have unwelcome, even harmful, side-effects: The flow of data tracking a baby’s vital signs may fuel unwarranted anxiety, even panic. Some parents have raced babies to the emergency room, needlessly, due to readings off these devices.

Worse yet, these alert-emitting devices made by a dozen or so companies may, some experts fear, lead parents to think they can more safely bring babies to bed with them — a practice often known as co-sleeping, which medical authorities say is dangerous and have been trying to curb, without success, for decades.

“Our concern is that parents become complacent if they have the monitor on,” said Dr. Rachel Moon, the chairperson of the American Academy of Pediatrics SIDS task force and a pediatrics professor at the University of Virginia. “They would be more likely to say … ‘I have the monitor on, I’ll know if something bad is happening.’”

Moon said the pediatric academy does not outright say these devices are harmful but is worried about their use in unsafe sleep practices, among other things. The accounts of many mothers suggest her concerns are far from theoretical.

“My baby won’t sleep unless he’s touching me,” a mother posted on BabyCenter, a parenting website, about her use of Snuza, a device that clips on a baby’s diaper and tracks abdominal movements tied to breathing. Co-sleeping, she said, is “nerve wracking but I feel better about it when he’s wearing his monitor.”

“I know it’s usually recommended against because it can cause false security,” a parent who co-sleeps posted on Reddit about a wearable monitor. “I like having a little extra reassurance.”

Many of these companies say they care about safe sleep and do not recommend their devices be used to ease fears about bed-sharing. In some cases, their user manuals include warnings against this practice, though pediatricians say these cautions should be more prominently displayed.

Device makers steer clear of explicitly saying their devices reduce the risk of SIDS, but nearly all of their websites refer to SIDS in ways that are impossible to ignore or publicize their dedication to curbing infant sleep deaths. Google the words “co-sleeping monitors” or “SIDS monitors” and an array of these devices turns up on the screen.

Meanwhile, federal authorities who regulate such products have been slow to address deep concerns about how these devices are marketed to anxious parents.

The Food and Drug Administration stresses that it has not approved any monitors to prevent such infant deaths and that parents should always follow safe sleep guidelines. “The FDA wants to make clear that the FDA has not authorized any device, including pulse oximeters, for the prevention of Sudden Infant Death Syndrome (SIDS),” said Carly Kempler, an agency spokesperson, in an email.

However, there is no evidence that the agency has required any of the companies marketing these devices to more prominently feature similar warnings — on their websites or marketing materials. The FDA would not comment directly on what, if any, restraints it has imposed on how companies promote these products to parents.

The Federal Trade Commission, which oversees false and misleading marketing claims for over-the-counter health products, has also taken a hands-off approach to these baby monitors. The agency said it has never brought an action against a company that makes these new types of monitors.

The government’s blind eye to the role of these devices in co-sleeping is notable, given the focus in recent years on identifying bed-sharing as a hidden reason behind many of the 3,400 or so infants who die tragically each year in their sleep.

Data from the Centers for Disease Control suggest close to one-third of these deaths could be explained by accidental suffocation due to such high-risk sleep environments, although it is unclear if this is an accurate assessment of how often parental behavior played a role in infant sleep deaths. A Globe study finds great variability in the reliability of the data and how states determine causes of death. An autopsy also cannot distinguish if a fatality was accidental suffocation or SIDS, so death reports suggesting asphyxiation are largely based on parents acknowledging they co-slept or on what authorities witnessed as unsafe sleep conditions.

The government’s efforts to reduce these tragedies over the past two decades have largely stalled — and failed to lower the stubbornly grim mortality rate. That’s partly because the medical causes of SIDS remain uncertain and partly because behaviors around safe sleep have proven to be largely intractable, with government warnings about the risks of co-sleeping often ignored. Studies show a majority of parents admit to some bed-sharing.

There is no doubt that accidental suffocation can be a risk when parents sleep next to their small babies, due to the potential they could roll over them. And for some babies with brainstem abnormalities or other intrinsic vulnerabilities, even just a temporary obstruction of their breathing can set off a chain of events leading tragically to a SIDS death.

For these device companies, parental fears about sudden sleep deaths offer a market opportunity. Owlet, the maker of a sock device, and one of the leading companies in the wearable baby monitor market, has said it has tracked more than 1 million babies since its founding a decade ago. Its top executive estimates that the global market for technology related to child-health data and services could reach $81 billion by 2025. The head of Masimo, a California-based medical technology company that released its wearable baby monitor this year, has told investors that he expects the device could become a business of “a couple of hundred million dollars a year.”

For some parents these newest high-tech monitors can allay fears that have haunted mothers and fathers for generations.

Caryse Zeidel, a mother of two from Marlborough, bought the Owlet Smart Sock in 2021 because she was worried about SIDS and wanted to closely monitor her first child, who had heart complications as a newborn.

At about $300, the sock, which contained an oxygen and pulse rate sensor, was a pricey purchase. But SIDS is “a fear of every new mom,” Zeidel said.

Zeidel said her children often slept in their own beds, but when they had colic or reflux or just struggled to sleep alone, she would bring them into her bed. On those occasions, she said, the monitor, “did give me a little more peace of mind.”

But she emphasized that she didn’t buy the sock to facilitate bed-sharing, and she firmly believes the devices shouldn’t be relied on to keep infants safe.

Social media sites are filled with testimonies from parents who praise these devices for making it feel safer to share beds with their babies.

Kelly Pretorius, a nurse and postdoctoral fellow at Indiana University, studied a 17,000-member Facebook group in 2019 as part of her research into parents and infant sleep deaths.

“I 100 percent found evidence in my Facebook study of parents practicing what we would classify as unsafe sleep for the American Academy of Pediatrics,” Pretorius said. And many were doing it with monitors “because it made them feel more comfortable,” she said.

One alarm that mattered

This new generation of monitors is not like the old-fashioned walkie-talkies, or the modern, high-tech video cameras placed near cribs. These wearable monitors can track babies’ vital signs wherever they sleep but also include sophisticated sensors that relay information instantaneously to a parent’s smartphone.

Katie Clark, a parenting blogger and mother of three from Colorado, told the Globe that she got the Owlet because her sons had respiratory issues. She thought the device was a fantastic idea and hoped it would alert her if they had any breathing problems at night.

Katie Clark with her son Oliver when he was an infant in 2010. When Clark accidentally fell asleep with Oliver in bed, she said, an Owlet baby monitor woke her up, alerting her that Oliver’s blood-oxygen level had dropped after he became wedged between her and the mattress. Family Photo

When her boys were small, she signed on to be one of the many “affiliates” that the company enlists to review and build awareness of its device. Clark touts the device on her website and has earned a small fee from sales, though she says she would never let money influence her honest assessment of a product.

Clark said the monitor kept her informed about her middle son’s apnea and respiratory issues, providing her notifications of her baby’s oxygen saturation levels and heart rate. But she also credits it with helping her avoid what could have been a potentially disastrous co-sleeping situation.

Clark said she occasionally co-slept with her children but had tried to avoid it with her middle son, who was smaller and had health concerns. But one night in 2015, when she was particularly tired and her infant son had been struggling with reflux, she took him into her bed and burped him as he lay on her chest. They fell asleep. The jarring sound of the Owlet alarm woke her up, sometime later, she said, warning her that her son’s oxygen level had dropped too low.

In her blog a few weeks later, Clark recounted how this alert went off when she found her son wedged under her with his face in the mattress, potentially suffocating.

“I don’t share this to try and make you buy one of these monitors. I share it because I am so grateful that I had [it] when I needed it,” Clark wrote.

In an interview with the Globe this fall, Clark said she wouldn’t advise parents to use the monitors as an excuse to sleep unsafely.

“If you rely too much on outside things, you take more risks,” Clark said.

Unclear medical benefit

But can these monitors alert parents to an impending SIDS crisis and enable them to intervene in a life-saving way? Scientists are deeply skeptical.

A study done more than two decades ago on some 1,000 infants sent home with vital-sign monitors suggested that severe cardiorespiratory events are not likely to be immediate precursors to SIDS, and these type of devices may have limited value given the complex and rapid cascade of problems linked to a SIDS death.

That study, however, was not designed specifically to determine whether use of these monitors decreases the rate of SIDS. Researchers say there has not yet been an updated, similar study looking at these home monitors for babies.

“There isn’t a shred of evidence these monitors have prevented any disease. We have SIDS in hospitalized infants. So it may be that if you are going to go you can’t be saved,” said Dr. Eliot Katz, a pediatric pulmonologist who was at Boston Children’s Hospital for many years and now works for Johns Hopkins Medicine in Florida. “At the end of the day I think the companies are sort of playing on parents’ fears, when they are trying to argue they are providing a safety mechanism when it hasn’t in fact been proven.”

On Owlet’s website, the company’s products appear alongside accounts of its fund-raising for SIDS research and its work with foundations led by grieving parents. FetalPlus promises to send alerts to parents on their smartphones if a baby encounters any of the risk factors for SIDS, including babies sleeping on their stomachs or in overheated rooms. Snuza, a South African company prominently features satisfied consumers saying the device eased their worries about SIDS.

This kind of marketing can be indirect but still effective.

“I know exactly what they are doing,” said Frances Miller, an expert on FDA regulations and professor of law emerita, Boston University School of Law, when a reporter described a banner that had been on Owlet’s website for SIDS research fund-raising. “They are skating up to the line.”

Frances Miller is a retired law professor at Boston University School of Law and an expert on FDA regulation. Suzanne Kreiter/Globe Staff

An implied benefit can be a strong motivator for anxious parents, said Chris Lavanchy, engineering director who studied these monitors at the ECRI Institute, a nonprofit that evaluates medical technology.

“The marketing was very powerful in some cases,” Lavanchy said. “While it was never explicitly stated that these devices would either identify or prevent SIDS, they definitely suggested it or gave you that impression.”

Kurt Workman, the CEO of Owlet, said the company wants to be part of solving the SIDS mystery with the data it is collecting from Owlet users and research it is funding.

“One day we hope that our data helps shed light on that. That we can be a source for research,” said Workman, who started the Utah-based company with some of his engineering classmates while they were at Brigham Young University. In 2022, Owlet made $69 million in revenue, although its operating expenses exceeded that, according to its publicly available financial statements. It has yet to have a profitable year since going public in 2021.

Workman rejected the idea that Owlet’s monitors could encourage unsafe sleep practices. He said a company survey found that one in five Owlet users failed to follow safe sleep guidelines, a much lower frequency than in the general population. Surveys done by the federal government and academics estimate more than half of mothers bed-share or fail to follow infant safety sleep guidelines.

FetalPlus did not respond to the Globe’s questions. A spokesman for Snuza said the company does not claim or market its devices as helping to prevent SIDS and does not recommend bed-sharing when using its devices.

Some clinicians said federal regulators should be doing more to require these companies to alert consumers about safe sleep and the limits of these devices when it comes to sudden unexpected infant deaths.

“Our federal agencies are slowly playing catch-up in understanding the need to regulate these products,” said Pretorius, the nurse who has studied parent attitudes about sudden infant deaths. “Infant sleep products and infant monitoring products — that tends to be how mothers are coping.”

In 2021, the Food and Drug Administration did warn Owlet that its Smart Sock was a medical device, largely because it included diagnostic alarms, therefore needed regulatory approval that it did not have. The company pulled that monitor off the market as it sought FDA clearance, which it received in November.

This nascent regulatory environment has left some companies hopeful they will eventually be able to tell parents that their devices will help ease their fears about SIDS.

Joe Kiani, the founder of Masimo, which launched a baby-foot monitor this summer called the Stork, was bold about his marketing ambitions if the device gets FDA approval.

“Right now in the US we can’t tell parents this can help detect SIDS . … We have to be careful how we phrase things. We can’t be open about all its capabilities,” Kiani said during the call with investors in August. “But once we get the FDA clearance, we can really go to town and really take the covers off.”

A Masimo spokesman told the Globe that the company believes its pulse oximetry technology can detect physiological deterioration prior to SIDS and will be working to get FDA approval “for a SIDS indication in the future.”

Even though these products are expensive, some mothers with limited incomes are willing to stretch their budgets to attain the peace of mind these products promise.

Jassenia, a 27-year-old Boston mother who only provided her middle name to protect the privacy of her family, lost her 4-month-old daughter in 2018 while they were co-sleeping. There was little room in the apartment she shared with her mother to keep a crib nearby, and her daughter had reflux. She felt more comfortable sleeping next to her baby.

Distraught over her daughter’s death, she worried, when she got pregnant again, that her anxiety would make it impossible for her to sleep.

Several family members donated money so that she could pay half of the $300 price tag for an Owlet monitor. A foundation set up by a Louisiana mother who lost her daughter to SIDS and works with Owlet to give out these monitors covered the remaining cost.

Her second daughter slept with Owlet’s sock monitor for the first year of her life, and Jassenia said she was more vigilant about sleeping separately from her baby. But she did on occasion lapse into bed-sharing when she was exhausted and took solace in the knowledge that the device might offer some protection.

“I was still nervous and I would still wake up to check on her,” Jassenia said. “It just gave me a bit of a peace of mind.”

Read part 1 and part 2 of this three-part Boston Globe Spotlight Team series about the government’s controversial approach toward trying to curb co-sleeping and SIDS.

Tips and feedback can be sent to reporter Deirdre Fernandes at Or they can be sent to the Boston Globe Spotlight Team at, or by calling 617-929-7483. Mail can be sent to Spotlight Team, the Boston Globe, 1 Exchange Place, Suite 201, Boston, MA. 02109-2132.

Deirdre Fernandes can be reached at Follow her @fernandesglobe. Liz Kowalczyk can be reached at