You Are Not Alone: Japanese Kids More Likely Than U.S. Peers to Spend Night in Parents' Bed

For the most part, American parents tend to think it's bad for their kids to share a bed with them at night. But in Japan, kids are nearly four times as likely to sleep with the parents - and are no worse , according to a new study.

The study, published in the April edition of Archives of Pediatrics & Adolescent Medicine, shows that 59% of Japanese kids sleep three or more nights a week in their parents' bed. By contrast, about 15% of American kids climb in with their folks.

In the U.S., sleeping with the parents was associated with a greater incidence of waking up in the middle of the night, resisting the whole idea of going to sleep and generally more stressful sleep problems. In Japan, what's known as co-sleeping was only associated with frequent night waking - and even that was at a reduced level that's more common among American children who sleep by themselves at night.

The team led by Dr. Sara Latz found that most Japanese children have adult company and body contact when they fall asleep, and that fathers sleep separately from the rest of the family in 23% of the families studied.

And, for the most part, when Japanese kids sleep with their parents, it's for the whole night; only 11% of American kids who co-sleep with their parents are there for the whole night.

The researchers believe that cultural differences, and not anything biological, account for the differences between the kids in the two nation. "The experience of the Japanese families indicates that cosleeping per se is not associated with increased sleep problems in early childhood," the researchers write.

The study was based on parents of healthy kids between 6 months and 4 years old who live in urban areas of both countries. All of the kids were breast-fed and lived in two-parent, middle-class households.