Clinical Reference Systems: Pediatric Advisor 10.0

The Preferred Position: On the Back (Supine)

In 1992 the American Academy of Pediatrics (AAP) recommended that all healthy infants be positioned for sleep on their backs (supine) or on their sides for the first 6 months of life. In 1996, the AAP recommended the back as being preferred over the side position. In 1992, only 30% of U.S. infants slept on their back or side. Now about 75% of U.S. infants sleep on their backs or sides.

Research Linking the Prone (Tummy) Position and SIDS

Most infants in the world are put to sleep lying on their backs. In the 1980s, research studies from Europe, Australia, and New Zealand showed that the supine sleep position reduces SIDS (sudden infant death syndrome) 20% to 67%. The prone position has a three to nine times greater risk of SIDS than the supine position. The side position has a two times greater risk of SIDS than the supine position. Although none of these studies were perfect, in 1992 the AAP recommended the supine position because of the 6000 to 7000 SIDS deaths each year in the U.S. Although this change in sleeping position won't eliminate all SIDS risk factors, it should reduce the number of SIDS deaths.

Reasons the Prone (Tummy) Position Might Increase SIDS

The on-the-stomach (prone) position puts pressure on a child's jaw bone. As a result, the airway in the back of the mouth becomes narrower. Also, if the child sleeps on a soft surface, the nose and mouth may sink in so the child breathes from a small pocket of stale air. In fact, the increased SIDS rate in countries such as New Zealand may be due not to the prone position alone but to placing children prone on sheepskin pads. Everyone now agrees that young infants should never be placed on waterbeds, sheepskin, soft pillows, bean-filled pillows, or other soft, spongy surfaces. These surfaces are also potentially dangerous when a child is placed in the crib on his back because he may roll over during the night.

Risks of the Supine (Back) Position

The main reason for the earlier recommendation of the prone position was the concern that if a child spits up or vomits while lying on his back, he could inhale (aspirate) and choke on the vomited material. This concern led to a change of recommendations from the supine to the prone position in the U.S. and Canada in the 1950s. However, the AAP has found no evidence to support the belief that choking occurs more commonly in the supine position than in other positions. Choking is an extremely rare cause of infant death in healthy, full-term infants. During the last 4 years, the rate of choking in infants has not increased.

The Exceptions: When the Prone (Tummy) Position Is Recommended

The American Academy of Pediatrics recommends the prone, or "tummy," position for infants in the following three categories:

• Infants with complications of gastroesophageal reflux (spitting up). These complications include recurrent pneumonia from aspiration, choking, interruption of breathing (apnea), or acid damage to the lower esophagus (esophagitis). While spitting up is common, these complications are rare.
• Infants with birth defects of the upper airway that interfere with breathing. Examples are a large tongue, a very small mouth, or a large and floppy larynx.
• Premature babies who are having difficulty breathing or require oxygen. (Research shows that premature babies breathe better in the prone position.) By the time they come home, most premature babies should sleep on their backs.

Any baby who needs to sleep prone must be placed on a firm sleeping surface.

Prone (Tummy) Position for Playtime

The back position is recommended for bedtime and naps. It is not necessary if your infant is awake. Yet many parents keep the infant lying on his back throughout the day. This can cause some flattening of the back of the head and also some decreased strength in the shoulder muscles. Avoid these side effects by keeping your infant prone for some of his playtime and waking hours. When in the crib, babies tend to turn slightly toward the side where they can see people. Therefore, every week reverse the direction you lay your baby in his crib.

Summary

Several years have passed since 1992, when the AAP recommended that infants sleep on their backs. Now over 75% of parents follow this advice. By 1995, national data showed a 30% drop in the SIDS rate. One study in Seattle showed a 50% drop in SIDS following an intensive sleeping- on-the-back campaign. Provide your baby an added margin of safety by placing him or her on the back for sleep. If you use a child care center, be sure they are aware of your preference.

Other ways to reduce the risk of SIDS are to use a firm mattress (avoid soft bedding), breast-feed if possible, and protect your infant from exposure to cigarette, cigar, or pipe smoke.