WASHINGTON — A House oversight committee has announced it is launching an investigation into infant inclined sleepers, the popular bassinet-like products reportedly tied to several baby deaths and the subject of a major recall earlier this year.

Reps. Elijah Cummings, D-Md., and Raja Krishnamoorthi, D-Ill., said in a statement that the Committee on Oversight and Reform was seeking a range of documents from manufacturers and the Consumer Product Safety Commission, among others, about how the product was developed and marketed.

Millions of inclined sleepers were sold over the last decade, and many parents swore by the product’s ability to get newborns to sleep. The product differs from traditional cribs by allowing babies to sleep at an angle of 30 degrees.

But in April, Fisher-Price, the product’s largest manufacturer, issued a recall in conjunction with the CPSC for 4.7 million units of its Rock ’n Play inclined sleeper after it was associated with more than 30 infant deaths. The CPSC said the deaths occurred when babies turned over while unrestrained or “under other circumstances.” Another company, Kids II, also recalled its inclined sleeper after it was associated with five deaths.

Fisher-Price invented the inclined sleeper category based on faulty beliefs about infant sleep and without medical safety testing or input from a pediatrician, and the company and regulators allowed the product to be sold despite questions about its safety.

The American Academy of Pediatrics has opposed inclined sleepers for several years, saying babies should sleep on their backs on flat surfaces.

Fisher-Price followed its recall by also pulling another inclined sleeper accessory, despite no reports of problems.