The country’s largest association of pediatricians is warning that a product designed to help infants sleep more soundly could be deadly.
The makers of weighted swaddles and sleep sacks liken them to a parent’s hand resting gently on an infant’s chest or to the sensation of “being held and hugged.”
But the American Academy of Pediatrics says placing weight on babies while they’re sleeping poses an alarming and potentially fatal risk — and the group is calling for a closer examination of the potential danger.
Weighted sleep sacks and swaddles could hypothetically increase the risk of sudden infant death syndrome by making it harder for babies to arouse themselves in response to hazards, such as lack of oxygen, the AAP said in a letter Thursday to the Consumer Product Safety Commission and ASTM International, a technical standards development organization.
“Why would anyone put a weight on top of a child’s chest — particularly a newborn?” said Dr. Michael Goodstein, a neonatologist and member of the AAP’s task force on SIDS. Infants’ rib cages are more elastic and flexible, so adding weight could also potentially compress their chests and affect their breathing, he said.
The Consumer Product Safety Commission has not put out any warnings about infant deaths linked to weighted sleep sacks or swaddles. An agency database lists one infant who died while wearing a weighted sleep sack, though it’s not clear whether the sleep sack played a role in her death. The 5-month-old girl’s father discovered she wasn’t breathing in March 2021, according to a report submitted to the agency by a medical examiner or coroner in Washington state. The baby had also been set down on an infant lounger, a pillow-like product that can pose a suffocation and asphyxiation risk. The brand of sleep sack wasn’t listed on the report.
Dreamland Baby and Nested Bean, which make two of the best-known weighted sleep sacks, maintain that their products are safe.
Tara Williams, the founder and CEO of Dreamland Baby, said the AAP’s safety concerns were “speculative” and added that there was no evidence that weighted sleep products were responsible for any reported deaths or injuries.
“We don’t have customers writing in saying, ‘I felt like my baby couldn’t roll, I felt like my baby couldn’t breathe.’ It just doesn’t happen,” she said. “Where is this coming from?”
Manasi Gangan, the founder and president of Nested Bean, said she remained hopeful that the AAP would change its position on weighted sleep sacks once the products were researched more thoroughly.
“The AAP has taken — and I understand why — an extremely conservative approach toward weighted blankets because of the popularity it has gained,” Gangan said. She later added, “There is no evidence to support that our products impair sleep arousal in response to physiological needs.”
There are no federal safety requirements or regulations for infant sleep sacks.
Williams is co-chairing an effort to create voluntary safety standards for infant wearable blankets — the broad term for sleep sacks and swaddles — through ASTM International, which develops standards for products through a collaborative process that is open to the public. The group working on wearable blankets includes industry representatives, consumer advocates, medical experts and Consumer Product Safety Commission staff members, and is examining both weighted and non-weighted products.
In its letter, the AAP announced that it is opposing the creation of a voluntary safety standard for weighted infant sleep products. Such a standard “will send parents and caregivers the incorrect message that these unnecessary products are safe,” the AAP said in its letter.
Consumer Product Safety Commission Chair Alex Hoehn-Saric said in a statement that the agency was aware of the AAP’s concerns and that the agency’s staff “is taking a close look at these weighted products as part of a larger examination of wearable blankets.”
He urged parents “to shop carefully and consult with their pediatrician before buying any product that claims to improve baby health or help with sleep.”
ASTM International said in an email that it valued input from all stakeholders and would ensure that the AAP’s letter “is given due consideration.”
The AAP first advised parents against using “weighted swaddles, weighted clothing or weighted objects on or near the baby” a year ago, when it updated its safe sleep recommendations, saying the items “are not safe and not recommended.”
Nested Bean and Dreamland Baby were created by entrepreneurs who said they were inspired by their own experiences as mothers of newborns who wouldn’t sleep. Nested Bean's signature product is a sleep sack with a small weighted pouch that rests in the center of a baby's chest, which weighs 1 ounce for babies up to 6 months old. The company has attracted venture capital investment, and it had $15 million in sales in 2019, according to Forbes. The company declined to release recent sales figures.
Dreamland Baby’s products are filled with plastic beads that distribute weight across infants’ torsos. They are heavier, weighing nearly 13 ounces for babies up to 6 months old, and they spread the weight across a larger surface area. The company grew quickly after it launched a Kickstarter campaign and appeared on “Shark Tank” in 2020. Dreamland Baby reached $10 million in revenue in 2021, it said in a news release, with more than 500,000 products having been sold to date.
Dreamland Baby and Nested Bean have put safety at the forefront of their sales pitches: They say that their products are supported by medical professionals, research and testing and that they meet rigorous safety standards.
In its letter this week, the AAP points to preliminary data from an industry-commissioned study from March to support its concerns about weighted sleep products.
The study, commissioned by Nested Bean and conducted by a private engineering firm, doesn’t conclude that weighted infant sleep products are either dangerous or safe. And its scope is limited: The study encompassed only five infants, used a two-minute test window, and wasn’t peer-reviewed.
But the AAP described the preliminary data as “evidence that the use of weight sleep products on infants can lead to lower oxygen levels, which if sustained, may be harmful to the developing infant’s brain.”
In the study, obtained by NBC News, researchers placed oval weights on infants’ chests, similar to the design of Nested Bean’s products, and gradually increased the weight from 1 ounce to about 9.5 ounces.
“As chest load increased, pulse rate increased and SpO2 generally decreased,” the study concluded, referring to the level of oxygen in the blood. The decrease in oxygen level was statistically significant for all weights tested, while the increase in pulse rate was statistically significant for weights over 1 ounce. One baby repeatedly tried to remove the weight as it became heavier.
Average oxygen saturation levels remained above 95%, the range generally considered healthy for infants and adults, the study said. But it noted that there was the potential for oxygen saturation levels to “decline into unsafe levels” during longer sleeping periods. Researchers also noted the potential for infants to experience fatigue — another risk factor that could compromise infants’ ability to breathe, said Dr. Rachel Moon, the chair of the AAP’s task force on SIDS.
“It’s not the level, it’s the trend I’m worried about,” Moon said. “Why didn’t they let it go more than two minutes? You’d want to know what’s happening over 30 minutes, two hours.”
Gangan, the Nested Bean president, said the study gave no indication that her company’s products were unsafe. She said its short test window was modeled on other research involving babies. “It is normal for SpO2 to fluctuate within healthy ranges, even when no load is applied,” she said in an email.
Gangan pointed out that infants regularly experience pressure from tight car seat straps across their bodies and “have hands or caregiver palms of various weights be placed on their bodies including on their chests.”
The AAP said in its letter this week that federal regulators and ASTM should take a “precautionary approach” towards new sleep products, rather than wait and see if they cause harm.
The AAP added that it wanted to “avoid a repeat of what happened with inclined sleepers, in-bed sleepers, and other novel sleep-related products,” which were ultimately linked to more than 100 deaths.
“Waiting for the emergence of confirmatory data about these concerns while these products proliferate is an unacceptable outcome when each of those data points will be a family whose lives are forever marked by unfathomable tragedy of their infant dying from a sleep-related death," the AAP said.
In interviews, Goodstein and Moon said more rigorous, peer-reviewed research is needed.
“You should prove safety before you put a product out there,” Goodstein said. “You shouldn’t be proving it after kids die.”
Both Dreamland Baby and Nested Bean said that they are pursuing more in-depth research on the safety of weighted infant sleep products but that it will take time for these larger studies to be designed, completed and published in peer-reviewed journals.
Both companies have also continued citing the AAP’s general recommendations for safe sleep on their websites, even after the group advised against the use of weighted swaddles and other infant sleep products last year.
“First and foremost, all of our products have been designed according to the AAP’s Guidelines for Safe Sleep,” Nested Bean said on its website as of this week. Dreamland Baby’s website also cited the AAP’s safe sleep guideline in multiple blog entries, posted as recently as Tuesday, reiterating the group’s recommendations to place babies on firm, flat sleep surfaces.
But none of those links mentioned the AAP’s updated 2022 warning against using weighted sleep products for babies.
After NBC News asked Dreamland Baby about the omission, the company added a note to its website Wednesday: “The AAP updated their guidelines in June 2022, and are not currently approving any weighted sleep solutions.”
Nested Bean said in a statement that it removed all mentions of the AAP from its website last year and would address the link NBC News shared. “An older version seems to have resurfaced unintentionally on our website,” Gangan said in an email Wednesday. “This will be promptly addressed this week.”