FACT: This is not true – babies are actually safer on their backs. When a baby is on his or her back, the airway (trachea) is on top of the esophagus (the tube that carries food).  If a baby spits up while on his
or her back, the food and fluid run back into the stomach and not to the lungs. When a baby is on his or
her stomach, the esophagus (or food tube) is on top of the trachea and any food or fluid that is regurgitated or refluxed can more easily pool at the opening of the trachea, making it possible for the baby to aspirate or choke.
When babies sleep on their backs, their airways are more protected.