Who Gets It?

Small preterm infants are most likely to have primary sleep apnea of infancy. It sometimes occurs in larger preterm or full-term infants. It is less common in infants under the age of six months.

During the first month after birth it occurs in 84 percent of infants who weigh less than 2.2 pounds. The risk decreases to 25 percent for infants who weigh less than 5.5 pounds. It is rare in full-term newborns.

In preterm infants, primary sleep apnea of infancy tends to appear between the second and seventh day of life. It is rare on the first day of life. Its presence at birth is usually a sign of another illness.

A variety of medical conditions can cause primary sleep apnea of infancy or make it worse. These problems include:

A small percentage of children who die from sudden infant death syndrome (SIDS) have apnea symptoms prior to death. But primary sleep apnea of infancy has not been established as a risk factor for SIDS.