Sharing a bed with an infant may seem like a healthy option for parents, yet some researchers say it may be anything but. A recent study found co-sleeping linked with sudden infant death syndrome (SIDS). Because of this new evidence, the American Academy of Pediatrics (AAP) has recommended parents share a room with their infant babies, but not a bed.

Co-Sleeping Rates in 48 States

In a study conducted by researchers from Yale University School of Medicine, lead researcher Eve R. Colson, M.D., and colleagues spoke with 18,986 participants in the National Infant Sleep Position study, an annual telephone survey in 48 states. Of the respondents, more than 84 percent were the mothers of babies and more than 80 percent were white. Almost half of the caregivers were ages 30 or older, had completed a college education, and earned a yearly income of at least $50,000.

What did the researchers discover? Among those who participated in the survey, 11.2 percent reported sharing a bed with their infant as a usual practice with a general increase in the practice from 6.5 percent in 1993 to 13.5 percent in 2010. This was especially true among black and Hispanic families.

"Compared with white infants, black infants are 3.5 times more likely to share a bed," the authors wrote. In fact, the practice is generally on the rise, with the percentage of black infants usually sharing a bed increasing from 21.2 percent in 1993 to 38.7 percent in 2010, and for Hispanic infants, the increase was from 12.5 percent in 1993 to 20.5 percent in 2010. White infants usually sharing a bed increased from 4.9 percent in 1993 to 9.1 percent in 2010, yet the rise here occurred during the earlier phase of the study (1993 to 2000), but not in the more recent period (2001 to 2010).

The factors more commonly associated with co-sleeping arrangements included a household income less than $50,000 and living in the West or the South.

Some Doctors Disagree

"The factors associated with infant bed sharing may be useful in evaluating the impact of a broad intervention to change behavior," the authors stated in a press release announcing their study.

Yet, not all pediatricians agree with the recommendation to discourage the practice and encourage solo sleeping as they disagree with the very findings of this new study.

"I find the report disquieting because evidence linking bed sharing per se to the increased risk for infant death is lacking," Abraham B. Bergman, M.D., of the Harborview Medical Center, Seattle, wrote in an editorial published in JAMA Pediatrics.

He is not alone. A British study from 1999 found no evidence to suggest bed sharing may be hazardous for infants of parents who do not smoke. The researchers began their study of infant sleeping practices in the United Kingdom by noting that in certain cultures where mother-infant co-sleeping arrangements are common, such as Japan and Hong Kong, the rates of cot death are low. To investigate sleep environments of 325 babies who died of SIDS as well as 1300 ‘control’ infants, the British researchers collected data from questionnaires, interviews, and medical records. Then, they evaluated risks and contributing factors for SIDS.

“There are certain circumstances when bed sharing should be avoided, particularly for infants under four months old,” the authors concluded. “Parents sleeping on a sofa with infants should always be avoided.” Nevertheless, they found co-sleeping to be acceptable and non-hazardous for infants.

"Equal time in counseling should be given to the benefits to bed sharing, such as more sleep for the parent, easier breastfeeding when the infant is nearby, ease of pacifier reinsertion, and the intangible satisfaction of skin-to-skin contact," Bergman wrote in his editorial. "In its admonition against bed sharing, the AAP has overreached."

Sources: Blair PS, Fleming PJ, Smith IJ, et al. Babies sleeping with parents: case-control study of factors influencing the risk of the sudden infant death syndrome. British Medical Journal. 1999.

Colson E, Willinger M, Rybin D, et al. Trends and Factors Associated With Infant Bed Sharing, 1993-2010. JAMA Pediatrics. 2013.