FDA Sends Warning Letter to Snoo Company, Publicizing Safety Concerns

In the warning letter on Monday, the FDA cataloged a number of issues the agency had with the company. Some of them concerned the fact that Happiest Baby had changed elements of the Snoo after receiving FDA authorization, without the agency evaluating the parts of the product that had been newly introduced or redesigned. 

The FDA had previously approved three proprietary sleep sack sizes for use with the Snoo: small, medium, and large. But, according to the agency, Happiest Baby later began to offer an extra-small sleep sack, marketed for babies as small as 4 pounds, and an extra-large sleep sack, marketed for babies 23 to 25 pounds, although the agency hadn’t yet evaluated the new swaddles’ dimensions and weight recommendations for safety. 

The potential problem with the extra-small sleep sack, according to the FDA, is that if it is too tight for the baby, it could restrict the baby’s breathing. And the concern with the extra-large sleep sack is that if it is too large for the baby, it can either ride up and cover the baby’s mouth or neck or allow the baby to break free from the swaddle and get into an unsafe sleep position. Either way, says the FDA, the company should have submitted the expanded range of sizes to the agency for evaluation before putting them on the market.

Marketing the Snoo sleep sack for use by babies as small as 4 pounds—a lower birth weight than the agency had previously authorized—without prior FDA approval is problematic as well, because of the unique needs of premature babies, according to the letter. “This change in the intended patient population leads to a significant change in the device’s existing risk profile because lower birthweight/preterm infants are at an increased risk of SIDS,” the agency wrote. “FDA would expect to review additional data in a premarket submission to evaluate the impact of these changes.”

The FDA also noted that the company has been marketing the Snoo as part of a “hospital bundle,” although the FDA authorization had only applied to home use. The agency says the switch from home to hospital use changes how the bassinet would be used (on a rolling cart, for example) and how it would have to be cleaned (using harsh cleaners that could degrade components of the bassinet, for example). It also changes the characteristics of the babies who would be using them (particularly if it is used in a NICU setting), according to the agency.

The next problem that the FDA called attention to is perhaps of particular interest to parents who decide to buy a refurbished, “pre-loved” Snoo directly from the company (at significant savings compared with a new one). According to the letter, customers have complained about receiving dirty, stained, or soiled bassinets from the company, which the FDA says may put babies at risk of infection. Other Snoo customers have said their bassinet mattresses had mold that they couldn’t get out with cleaning. 

The FDA indicated in its letter that it has been communicating with Happiest Baby since summer 2025 about these quality control problems and related health risks to infants, and discussing how the company might address them. But the agency isn’t yet satisfied that Happiest Baby has fully resolved them. The FDA gave the company 15 days to respond to the letter and describe how the company was going to correct the problems it described. The company hasn’t publicly commented on its website or social media accounts yet.

In a statement to CR, Happiest Baby said parents using their small, medium, and large sleep sacks could “continue to use them safely and with confidence.” The statement also said that “regarding the XS and XL sleep sacks” the company was “committed to addressing the FDA’s questions regarding additional testing and approvals.” Happiest Baby also said it had ended the relationship with one of its refurbishers two years ago after determining it did not meet its standards.

“If a company is going to market a product as ‘FDA-authorized,’ then this claim needs to be entirely true,” says Oriene Shin, CR’s manager of safety advocacy. “After reviewing the FDA’s warning letter, it’s clear there are concerns with how Happiest Baby has been marketing the Snoo and its newer sleep sacks. This is especially concerning because the company included an extra-small sleep sack marketed for vulnerable premature infants weighing as little as 4 pounds. Parents deserve to have clear and accurate information, and Happiest Baby should reach out to its customers to inform them honestly about the FDA’s concerns and explain the steps the company is taking to address them.”

Aside from the FDA’s flags this week, customers have raised their own concerns and questions over the years, in forums like the Consumer Product Safety Commission’s SaferProducts.gov public database, and Reddit discussions. In several incident reports to the CPSC, parents expressed safety concerns such as the Snoo straps unexpectedly obstructing their baby’s face or moving to their baby’s neck, posing a suffocation risk. 

One parent who bought the Snoo “leg lift” accessory that raised one end of the bassinet up at a slight incline said they had a close call where the baby slipped down too far into the swaddle, which they said was the “original style of sleep sack”; the parent awoke to an alarm from the baby’s breathing monitor and took her out of the bassinet.

No lasting injuries were reported in any of these incidents.