Great progress has been made in preventing tragic Sudden Infant Death Syndrome (SIDS) since 1992, when it was recommended that all babies sleep on their backs. Although we still don't know the cause of SIDS, the simple act of putting babies on their backs to sleep has reduced its occurrence by more than 50 percent.

Other modifications of the environment also make a big impact in preventing SIDS. (see below) Even with this decline, about 2,500 babies die each year from SIDS.

The October issue of a leading pediatric journal published a study showing that simply having a fan in the baby's room greatly lessens the chance of SIDS. In fact, this study found that the risk of SIDS was 72 percent less than if there was no fan in the room. Having an open window in the room reduced the risk a little, but not nearly as much as a fan. The authors believe that fans work because they prevent the baby from re-breathing their exhaled carbon dioxide, which current theory holds as a major contributor to SIDS. The authors also point out that the fan will not chill the baby but will merely recirculate air so the baby does not become chilled.

Putting babies on their back is the mainstay in prevention, but sleeping babies who roll over onto their stomachs do not need to be repositioned to their backs. Avoiding bed sharing remains controversial. However, studies find that bed sharing places babies at significant risk of SIDS because of suffocation. Sleeping with the baby on a couch poses the highest danger, but multiple bed sharers, smoke in the environment, and adults who either consume alcohol or are overtired also furthers the risk of SIDS. Interestingly, infants who sleep in the same room as the parents, but not in their bed, have the lowest risk of SIDS.

Soft surfaces, either in a crib or an adult bed, are particularly hazardous because the baby's nose and mouth can get completely covered by this soft bedding. (This supports the rebreathing of carbon dioxide theory as a cause of SIDS). Thus, soft pillows, mattresses or mattress coverings such as quilts, comforters, bumper pads and loose blankets should not be used where a baby sleeps. A firm crib mattress covered by a fitted sheet is best. In addition, the room should not be too warm.

Recently, several studies found that pacifiers have a protective effect. The reason is not clear but may be that pacifiers help to keep the air passages open and thus reduce decreased air flow. However, it is not recommended to force a baby to use a pacifier or to reinsert the pacifier if it falls out of the mouth when the baby is asleep.

What has not changed is that home apnea monitors for routine use do not effectively prevent SIDS and are therefore NOT recommended to be used for this purpose; immunizations do not increase the risk of SIDS; breastfeeding may be protective; and premature babies, like full time babies, should be placed on their backs when put to sleep.

The opinions expressed are solely those of the writer. Robert A. Dershewitz, M.D., Sc.M., FAAP, is a pediatrician at Healthy Kids Care Center in St. John and is affiliated with The Community Hospital in Munster.