The House Oversight Committee said Tuesday it was 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 E. Cummings (D-Md.) and Raja Krishnamoorthi (D-Ill.) said in a statement that the committee was seeking a variety of documents from infant-product 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 past 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 about 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, according to a review by The Washington Post, 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, signaling a full retreat from the product category it had once championed.

A third company, Dorel Juvenile Group, last month launched its own recall despite no injuries or deaths, asking consumers to stop using the Eddie Bauer Slumber and Soothe Rock Bassinet and Disney Baby Doze and Dream Bassinet.

But inclined sleepers remain legal to buy and sell in the United States.

That could change. Bills introduced last month in the House and Senate would ban all infant sleeping devices with an incline of greater than 10 degrees, matching safety regulations in Canada.

The CPSC is studying what it should do about inclined sleepers. On Tuesday, agency officials joined industry representatives and others to discuss whether changes to a voluntary standard for inclined sleepers could improve the product’s safety.