Safe Sleep and Sudden Infant Death Syndrome (SIDS)

Sleep-related causes of infant death are those linked to how or where a baby sleeps or slept. These deaths are due to accidental causes, such as suffocation, entrapment, or strangulation. Entrapment is when the baby gets trapped between two objects, such as a mattress and a wall, and cannot breathe. Strangulation is when something presses on or wraps around the baby’s neck, blocking the baby’s airway. These deaths are considered Sudden Unexpected Infant Death (SUID)

SUID is a term used to describe the sudden and unexpected death of a baby less than 1 year old in which the cause was not obvious before investigation. These deaths often happen during sleep or in the baby’s sleep area. 

Sudden Infant Death Syndrome (SIDS) is one type of SUID. SIDS is the sudden death of an infant younger than 1 year of age that cannot be explained even after a full investigation that includes a complete autopsy, examination of the death scene, and review of the clinical history. 

In Santa Clara County, most infant deaths were identified within an unsafe sleep environment and not considered a SIDS event. 

Infant deaths due to unsafe sleeping practices can be prevented. Every parent and caregiver needs to be aware of and follow these SAFE sleeping guidelines:

  • Babies need to sleep alone in a crib or bassinet with a firm mattress and a well-fitted sheet.
  • Babies should be put to sleep on their backs during naps and at nighttime.
  • Babies should not be placed on their sides to sleep because they may accidentally roll onto their stomachs and suffocate.
  • Babies should not sleep on adult beds, chairs, sofas, waterbeds, cushions, or nursing pillows. 


Safe Sleep Guide


Guide (English)

Guide (Spanish)

Guide (Vietnamese)  ​


Safe Sleep Recommendations 

Remember the ABCs

Alone: Always make sure the baby is alone in the crib. No toys, pillows, crib bumpers, or any other soft objects should be in the sleeping area.

Back: The baby should always be placed on their back.

Crib: The baby should be placed in a safety-approved crib that has a firm mattress covered by a tightly fitted sheet. 


Safe Sleeping Guidelines

  • Always place the baby on their back when putting the baby to sleep.

  • Use a safe sleeping surface. A great example is a safety-approved crib that has a firm mattress covered by a tightly fitted sheet.

  • Remove all soft objects, crib bumpers, toys, and any loose bedding from the baby’s sleeping area.

  • Do not smoke or let anyone else smoke around your baby or the baby’s sleeping area.

    • The smoke can be trapped in the sheets, toys, crib bumpers, and clothes of the baby, which has harmful effects on its health. 

    • Thirdhand smoke clings to clothes, furniture, drapes, walls, bedding, carpets, dust, vehicles and other surfaces long after smoking has stopped. The residue from thirdhand smoke builds up on surfaces over time.

  • Room Share, do not Bed Share

    • Room Sharing is when you and the infant sleep in the same room, but do not share the same sleeping surface. 

    • Bed Sharing is when you and the infant share the same sleeping surface. 

      • An example of Bed Sharing is sleeping in the same bed with the baby, also called Co-Sleeping.


  • Avoid putting your baby to sleep on sofas, cushions, chairs, and waterbeds.

    • Sleeping with the baby on a sofa or chair is the leading cause of infant suffocation in our county, according to the Santa Clara County Child Death Review Study.

  • Room temperature

    • If the room temperature is comfortable for you, it will be for the infant as well.

How To Use a Blanket while Practicing Safe Sleep

  • First, orient your infant so that the feet are positioned facing the end of the crib. 
  • Second, ensure that you are using a thin blanket, not a thick one. 
  • Third, the blanket should not reach higher than the baby’s chest.
  • Last, don’t forget to tuck the sides and end of the blanket underneath the mattress! 

Resources for Safe Sleep  

  • SIDS: Me and My Family — The California Department of Public Health’s (CDPH) webpage with information about SIDS and a link to “Safe Sleep Environments for Infants” 
  • About SIDS and Safe Infant Sleep — The U.S. Department of Health and Human Service’s Safe to Sleep campaign’s website with detailed information and facts about SIDS and Safe Sleep.
  • Safe to Sleep Campaign Materials — The Safe to Sleep campaign offers a variety of printable materials to help share safe infant sleep messages aimed for a variety of audience ethnicities and relationships, including grandparents.
  • How to Keep Your Sleeping Baby Safe: AAP Policy Explained — The American Academy of Pediatrics' webpage with recommendations for safe sleep

Videos on Safe Sleep 


Safe to Sleep—webpage “About SIDS/Safe Infant Sleep”

CDC—webpage Center for Disease Control

AAP—Task Force on Sudden Infant Death Syndrome 

NIH– National Institute of Health’s Safe to Sleep Campaign

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