Goodnight moon, hello Mom and Dad

Some researchers decry the practice of permitting babies and young children to sleep in the same bed as their parents do, warning of its potential to smother youngsters, both physically and emotionally. Others regard this arrangement, known as co-sleeping, as a way to build strong families and emotionally secure children.

New data suggest that this debate is too simplistic. Two contrasting types of co-sleeping exist in the United States, say Meret A. Keller and Wendy A. Goldberg, both of the University of California, Irvine.

If co-sleeping begins after an infant reaches age 1 and in response to the child’s bedtime struggles, sleep is often disrupted for everyone in the bed and family tensions are increased, the psychologists hold. However, co-sleeping generally proceeds smoothly when it begins within the first few months of an infant’s birth and continues into toddlerhood, Keller and Goldberg report in the December 2004 Infant and Child Development.

The researchers surveyed 83 mothers of California preschoolers. Of that number, 32 said that their child had always slept in a separate room, 28 reported routine co-sleeping that began during the child’s infancy, and 23 said that co-sleeping began around age 1 or later in response to the child’s sleep problems.

Intriguingly, mothers reported that preschoolers who began co-sleeping as infants exhibited more self-reliance and social independence—such as settling disputes with playmates on their own—than did those who slept alone or started co-sleeping at later ages.

Compared with either group of co-sleepers, solitary sleepers displayed several signs of greater personal independence. These consisted of falling asleep earlier, sleeping through the night more often, and weaning from breast-feeding at earlier ages.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.