Sudden Infant Death Syndrome (SIDS)

Last Updated 11/02/2020

Authors:Reshma Amin, MD; Kim French, MSDA, CAPPM, FCCP; De De Gardner, DrPH, RRT, FCCP

About Sudden Infant Death Syndrome (SIDS)

Sudden infant death syndrome (SIDS) is the sudden, unexpected death of an infant younger than 1 year of age. The cause of death is unknown, despite years of research. Factors such as sleeping position, place, and tobacco smoke are associated with SIDS.

Key facts about SIDS

Reduce the risk of SIDS for your baby by doing the following:

  • Lay your baby on his or her back to sleep.
  • Do not share a bed with your baby.
  • Do not expose your baby to any type of smoke. Don’t smoke or breathe in secondhand smoke if you’re pregnant.

How common is SIDS?

SIDS is the leading cause of unexpected death among infants in developed countries. In 2017, 1400 infants in the United States died from SIDS. SIDS is more common in boys than girls. American Indian, Alaskan Native, and Hispanic infants are more likely to die from SIDS than non-Hispanic white infants. SIDS is also more common in premature infants.

Why does SIDS happen?

Although risk factors have been identified, the cause of SIDS is unknown. The risk of SIDS is higher when any of the following occur:

  • If your baby is born prematurely—before 38 weeks of gestation—their risk of SIDS increases up to 4 times compared with infants born at full term.
  • You lay your baby to sleep on his or her stomach.
  • Your baby sleeps with soft objects and loose bedding.

Putting your baby to sleep

Putting babies to sleep on their backs on a firm bed reduces the risk for SIDS. The American Academy of Pediatrics recommended this in its 1992 Back to Sleep Campaign for all healthy infants under 1 year of age. Since this recommendation, SIDS rates have dropped by more than 50%.

Some parents are worried that their baby will develop a flat spot on the back of their heads from lying on their back all the time. This condition is easily treatable by allowing for more “tummy time” while your baby is awake during the day. Many parents are worried that their baby will choke if they are sleeping on their backs. However, there is no increased risk of choking for healthy infants who sleep on their backs. Keep soft objects and loose bedding away from the sleep area to reduce the risk of SIDS.

For more information

For more information about SIDS, see the Centers for Disease Control and Prevention SIDS website.