The number of parents who sleep with their babies is increasing significantly in the United States even though the practice remains highly controversial, with proponents saying that it helps mothers breast-feed and bond with their children and opponents warning that it increases the risk of suffocating infants.
The percentage of babies sleeping with a parent or another caregiver rose from 5.5 percent in 1993 to 12.8 percent in 2000, according to the first attempt to gather national statistics on the trend. In a nationally representative telephone survey of 8,453 caregivers, at least half said their babies had spent some of the night sleeping on an adult bed in the previous two weeks. The survey was conducted by the National Institute of Child Health and Human Development, which is part of the National Institutes of Health.
The practice is especially common among younger and poorer women, those living in the South, African Americans and Asian Americans, according to the National Infant Sleep Position Study, which was released yesterday.
A second study found that about half of babies in the District shared a bed with a parent or another adult. For that study, conducted between 1995 and 1996, researchers interviewed 369 mothers when their infants were between 3 and 7 months and again when the babies were 7 to 12 months old. Eighty-two percent of the women surveyed were African American.
Both studies were published in the January issue of the Archives of Pediatrics and Adolescent Medicine.
While neither study examined why women elect to sleep with their babies, "the practice is clearly strongly influenced by culture," and the custom of taking a child into the bed is typically passed down through generations, said Marian Willinger, who led the national study. "Certainly breast-feeding promotes bed sharing, and breast-feeding has been increasing."
The practice has also been promoted by advocates of more "natural" child-rearing and by some researchers who say it helps babies become happier and more secure.
"The infant wakes up in the middle of the night, and instead of being in a crib all alone there's the mother and father to cuddle with. The child is learning the parent is there for them," said Martin E.P. Seligman, a professor of psychology at the University of Pennsylvania and author of "Authentic Happiness: Using the New Positive Psychology to Realize Your Potential for Lasting Fulfillment." "It's what we call secure attachment."
James J. McKenna, director of the Mother-Baby Behavioral Sleep Laboratory at the University of Notre Dame in South Bend, Ind., said his studies have shown that the bodies of women and their babies are more in sync when they sleep together, which helps both sleep better.
"Babies are designed to feel the presence of their parents," he said. "It's only a very recent and very strange cultural innovation that babies would be sleeping apart from their mothers. It's very much a departure from the normal human pattern."
Jan Hunt, director of the Natural Child Project in Sunriver, Ore., which advocates bed sharing, was thrilled by the new numbers.
"For millions of years children slept with their parents," Hunt said. "It's really only in the past 125 years or so that we've had cribs for babies. Children need the companionship and security of their parents, especially at night even more so than during the day."
Opponents, however, warn that putting babies to sleep with an adult is a major risk factor for sudden infant death syndrome (SIDS), in which a seemingly healthy baby dies suddenly without apparent explanation.
"When we've looked at deaths of infants, we've found in many cases the baby was under a pillow or a mom or dad was on top of the baby directly, or maybe the dad's arm was across the baby's mouth," said Bradley Thach, a professor of pediatrics at the Washington University School of Medicine in St. Louis.
Last year, health officials in Baltimore determined that a significant number of infant deaths there occurred among children who were sleeping with an adult. "There's lots of other, safer ways to bond," said Peter Beilenson, city health commissioner.
Health officials in the District, who have also been trying to educate women about the potential dangers of bed sharing, said yesterday that the city gave away 1,600 cribs in the past two years to help low-income women.
Sleeping with children is especially risky if the parent is overtired, as is often the case with new parents, or if a parent smokes, drinks or uses drugs, experts said. Many say the safest way for babies to sleep is alone, on their back, on a firm mattress with no pillows or covers.
"Bed sharing puts babies at risk," said M. Edward Keenan, a pediatrician from Newton, Mass., who served on the American Academy of Pediatrics's sleep position task force. "It's a cultural norm in some cultures, but it raises the specter of putting your baby at risk."