As many as 1 in 10 day care centers are still using infant rocking sleepers that were recalled earlier this year after being linked to at least 32 infant deaths, according to a new study.

Adam Garber, who works at U.S. Public Interest Research Group, kick-started the study when he noticed that his son's day care was still using a Fisher-Price Rock 'n Play Sleeper that was recalled in April, Garber told Consumer Reports.

Fisher-Price recalled nearly 5 million sleepers after they were linked to several infant deaths. Shortly after, Kids II issued a recall for 700,000 sleepers of a similar design.

Garber asked his son's day care about the sleeper.

“Our day care provider, who cares deeply about the kids, was really confused,” Garber said. “She said she thought there had only been a warning about the Rock ‘n Play Sleeper and that as long as the product was properly used, and babies were buckled in, it would be fine.”

From June 20 to July 10, representatives with U.S. PIRG and the nonprofit Kids In Danger contacted more than 600 child care facilities via email and phone and asked whether they were using the recalled sleepers, according to a statement.

The study found that of the 376 facilities that responded, 1 in 10 were using at least one of the recalled sleepers. This included day cares in states that ban recalled products, such as Wisconsin and Texas, and states without such laws, such as Georgia.

"Even one dangerous sleeper is one too many for parents to be comfortable," the study said.

Garber told The Huffington Post that most day care staff simply hadn't heard that the sleepers had been recalled.

Part of the problem may have been confusing messaging from the U.S. Consumer Product Safety Commission and Fisher-Price, Garber said.

On April 5, the government and Fisher-Price issued an alert that the Rock 'n Play Sleeper had been linked to infant deaths, but said it was safe if used with restraints. A week later, the CPSC and Fisher-Price announced the recall. But the recall notice didn't clarify that infants could still suffocate even if strapped to the sleeper on their backs.

“Recalls don’t work well unless people get a clear and consistent message. And they especially don’t work well if manufacturers and the government fail to fully warn people about the risks of a product,” says William Wallace, manager of home and safety policy for Consumer Reports.

Garber said the findings highlight gaps in our current recall system.

KID and PIRG recommended the government work with recalling companies to include child care facilities in corrective action plans for toys and nursery products. The companies should double down on efforts to reach any users of the recalled sleepers, the groups said. Finally, they advocated for states to pass legislation banning recalled products in child care facilities.