by EBSCO Medical Review Board
(Crib Death; SIDS)


Sudden infant death syndrome (SIDS) is the unexpected, unexplained death of a child less who is younger than one year of age. SIDS is rare during the first month of life. It peaks at 2 to 4 months of age, then gradually decreases.


The exact cause is not known. It may be linked to problems with the parts of the brain that control functions like breathing, waking, and heart rhythm.

Area of the brain involved in regulation of breathing.
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Risk Factors

This problem is more common in infants who are less than 6 months of age. It is also more common in boys and babies who are Black, Native American, and Native Alaskan.

Other things that may raise the risk are:

  • Premature birth or low birth weight
  • Sleeping on the stomach or side rather than the back
  • Using quilts, blankets, pillows, or similar bedding items
  • Overheating from wearing too much clothing
  • Co-sleeping in the parent(s) bed
  • Lack of prenatal care
  • Exposure to tobacco smoke
  • Upper respiratory infections
  • Parental alcohol or drug abuse


A previously healthy infant does not respond and is not breathing after being placed in bed to sleep.


All possible illnesses and causes of death must be ruled out before a diagnosis of SIDS is made. A complete investigation will take place. It will include:

  • An autopsy
  • Investigating the area where the baby was found
  • Reviewing the baby and family's medical histories


Emergency treatment will be needed as soon as the infant is found. Infant CPR must be started. A baby who survives will need further medical care and evaluation to look for a cause.

Families of infants who do not survive will be referred to grief counseling and support groups.


The risk of this problem may be lowered by:

  • Getting regular prenatal care during pregnancy
  • Not smoking, drinking alcohol, or using drugs during pregnancy or after birth
  • Putting infants to sleep on their back until 1 year of age
  • Using a firm sleep surface
  • Avoiding soft materials and loose bedding
  • Sleeping in the same room as parents but on a separate sleep surface
  • Breastfeeding
  • Not putting too many clothing or blankets on an infant
  • Offering a pacifier at nap time or bedtime
  • Getting advised immunizations


Family Doctor—American Academy of Family Physicians 

Healthy Children—American Academy of Pediatrics 


About Kids Health—The Hospital for Sick Children 

Caring for Kids—Canadian Paediatric Society 


Sudden infant death syndrome (SIDS). EBSCO DynaMed Plus website. Available at: Accessed August 31, 2021.

Sudden infant death syndrome (SIDS). Kid's Health—Nemours Foundation website. Available at: Accessed August 31, 2021.

10/25/2016 DynaMed Plus Systematic Literature Surveillance. SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment Rachel Y. Moon, Task Force on Sudden Infant Death Syndrome. Pediatrics Oct 2016, e20162940; DOI: 10.1542/peds.2016-2940 .

9/26/2017 DynaMed Plus Systematic Literature Surveillance. Psaila K, Foster JP, et al. Infant pacifiers for reduction in risk of sudden infant death syndrome. Cochrane Database Syst Rev. 2017 Apr 5;4:CD011147.

Revision Information

  • Reviewer: EBSCO Medical Review Board Kari Kuenn, MD
  • Review Date: 07/2021
  • Update Date: 08/31/2021