Loading icon
Press enter or spacebar to select a desired language.
Health Information Center

Sudden Infant Death Syndrome

  • Cynthia M. Johnson, MA
Publication Type:


Sudden Infant Death Syndrome

(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.

brainstemhttp://services.epnet.com/getimage.aspx?imageiid=75387538si55550219.jpgsi55550219.jpgNULLjpgsi55550219.jpgNULL\\hgfiler01a\intellect\images\si55550219.jpgNULL77NULL2008-12-10325400Copyright © Nucleus Medical Media, Inc.

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
  • Using safe sleeping practices, such as:
    • Putting infants to sleep on their back until 1 year of age
    • Using a firm, flat sleep surface
    • Avoiding soft, loose bedding and soft objects
    • Sleeping in the same room as parents but on a separate sleep surface—until at least 6 months
    • Not bed-sharing or sleeping with the baby on couches, soft chairs, or cushions
    • Making sure the infant is on his or her back when wrapped up (swaddled)
    • Offering a pacifier at nap time or bedtime
  • Breastfeeding until at least 6 months
  • Not putting too many clothing or blankets on an infant
  • Not depending on home monitors to reduce the risk of SIDS
  • Getting advised immunizations




  • Sudden infant death syndrome (SIDS). EBSCO DynaMed Plus website. Available at: https://www.dynamed.com/condition/sudden-infant-death-syndrome-sids. Accessed August 31, 2021.
  • Sudden infant death syndrome (SIDS). Kid's Health—Nemours Foundation website. Available at: http://kidshealth.org/parent/general/sleep/sids.html. Accessed August 31, 2021.
  • How to keep your sleeping baby safe: AAP policy explained. American Academy of Pediatrics—healthychildren.org website. Available at: https://www.healthychildren.org/English/ages-stages/baby/sleep/Pages/A-Parents-Guide-to-Safe-Sleep.aspx.
  • 9/26/2017 DynaMed Plus Systematic Literature Surveillance. https://www.dynamed.com/condition/sudden-infant-death-syndrome-sids: 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.


  • Kari Kuenn, MD
Last Updated:

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.