New research out of St. Louis identifies the most dangerous places to let babies sleep. Washington University professor Brad Thach studied more than 100 infant deaths between 1994 and 1997, along with the lead researchers at St. Louis University. Thach says 75% of the babies were sleeping in places designed for adults. He warns against letting a newborn sleep on an adult bed, especially with sleeping parents who could roll against the child. Couches and other soft surfaces are also off limits.