For the overwhelming majority of mothers and babies around the globe today, cosleeping is an unquestioned practice. In much of southern Europe, Asia, Africa and Central and South America, mothers and babies routinely share sleep. In many cultures, cosleeping is the norm until children are weaned, and some continue long after weaning. Japanese parents (or grandparents) often sleep in proximity with their children until they are teenagers, referring to this arrangement as a river - the mother is one bank, the father another, and the child sleeping between them is the water. Most of the present world cultures practice forms of cosleeping and there are very few cultures in the world for which it would ever even be thought acceptable or desirable to have babies sleeping alone.

Cosleeping is practiced in a variety of ways around the world. In Latin America, the Philippines, and Vietnam, some parents sleep with their baby in a hammock next to the bed. Others place their baby in a wicker basket in the bed, between the two parents. In Japan, many parents sleep next to their baby on bamboo or straw mats, or on futons. Some parents simply room-share by putting the baby in a crib or bassinet that is kept within arm's reach of the bed. Most cultures that routinely practice cosleeping, in any form, have very rare instances of SIDS. SIDS occurrences are among the lowest in the world in Hong Kong, where cosleeping is extremely common.

Cosleeping is actually more common in the U.S. than most people believe. The typical American home has a room that contains a crib for the baby, and parents report that the baby sleeps in the crib. Yet when researchers ask specific questions about who sleeps where, it turns out that the majority of mothers sleep with their young children at least some of most nights. Parents present themselves as having babies who sleep alone, following the societal norm of the baby in the baby's room and the couple in the master bedroom, but that is not an accurate representation of what is really happening.

The Centers for Disease Control (CDC) in Atlanta collects data that provide information on all means of prenatal and well-baby stressors. Through this, we know that cosleeping is not unusual for American families at all. Roughly 68% of babies enjoyed cosleeping at least some of the time. Further analyses of the data show us that about 26% of infants coslept "always" or "almost always." Combining them with the babies who cosleep "sometimes," it appears that 44% of US babies from 2-9 months old are cosleeping in an adult bed at any given time.¹

Japan, another industrialized country, not only has one of the lowest infant mortality rates (less than 3 infants per 1000 live births compared with around 7 for the United States), but one of the lowest SIDS rates in the world (between .2 and .3 babies per 1000 live births compared with approximately .5 per 1000 infants for the US). The Japan SIDS Family Organization reported that SIDS rates continue to decline in Japan as maternal smoking approaches practically 0, and exclusive breastfeeding reaches around 70-75 % . In fact, one report shows that as bedsharing and breastfeeding increased and as maternal smoking decreased, SIDS rates decreased. This suggests yet again that it is not necessarily bedsharing, but how it is practiced, that can be dangerous.

Interestingly, it may be that Japanese bedsharing rates do not differ all that much from those in the US, but the cultural acceptance of cosleeping as the norm is very different. In 1998, 60% of parents said they practiced bedsharing in Japan, only about 16% more than US parents. This means that the practice of cosleeping does not necessarily vary a great deal from culture to culture, but rather that the social acceptance of cosleeping is what varies.