Baby’s Anatomy When on the Stomach and on the Back

Back sleeping does not increase the risk of choking. In fact, babies may be better able to clear fluids when they are on their backs, possibly because of anatomy. When a baby is in the back sleeping position, the trachea lies on top of the esophagus. Anything regurgitated or refluxed from the esophagus must work against gravity to be aspirated into the trachea. When a baby is in the stomach sleeping position, anything regurgitated or refluxed will pool at the opening of the trachea, making it easier for the baby to aspirate or choke.

Illustrations showing the back and stomach sleeping positions and the placement of the infant's trachea (tube to lungs) and esophagus (tube to stomach). Figure 1 shows the back sleep position in which the trachea lies on top of the esophagus. Figure 2 shows the stomach sleep position in which the esophagus in on top of the trachea.

Download 1200x600 resolution (JPG 346 KB)

Download from NICHD Flickr Albumexternal link

Image courtesy of the Safe to Sleep® campaign, for educational purposes only; Eunice Kennedy Shriver National Institute of Child Health and Human Development,; Safe to Sleep® is a registered trademark of the U.S. Department of Health and Human Services.

More Photos of Safe Sleep Environments