Definition of Sudden Death Syndrome (SIDS)

The sudden and unexpected death of an apparently healthy infant, usually under one year of age, which remains unexplained after a complete medical history, death scene investigation, and postmortem examination.

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(Note to instructor: SIDS is a diagnosis of exclusion. Before a SIDS diagnosis is given, a medical history, death scene investigation and autopsy must occur and all other causes of death must be ruled out.)

(Note to instructor: Autopsies are mandatory for children who die suddenly and unexpectedly in the State of Nevada.)

Facts About SIDS: What It Is

  • Leading cause of death of infants from one month to one year of age
  • Occurred as frequently in the 18th and 19th centuries as now
  • Cannot be predicted or prevented
  • Victims appear to be healthy prior to death
  • Death occurs very rapidly, usually during a period of sleep
  • None of the possible causes of SIDS should result in pain or suffering to the baby

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Notes to instructor:

  • SIDS is not something that is a recent phenomenon or that has recently been discovered. SIDS deaths have occurred for a long time.
  • There is no way to “screen” babies and determine if they are at risk for SIDS
  • SIDS cannot be prevented. Recommendations can only be made to reduce the risk or chance of a SIDS death. However, some people follow all the risk reduction recommendations and death still occurs.
  • Some people have been in the same room at the same time a SIDS death has occurred and did not hear the baby struggle. The death occurs quickly and SIDS infants do not appear to suffer any pain.

Facts About SIDS: What It Is NOT

  • NOT caused by external suffocation
  • NOT caused by vomiting and choking
  • NOT caused by DPT shots or other immunizations
  • NOT caused by sleeping parent rolling over onto the infant
  • NOT contagious
  • NOT caused by lack of love

I. General and Common Characteristics of SIDS Infants

  1. Age:
    • 90% of SIDS deaths occur before 6 months of age
    • 70% of these deaths occur between 2 and 4 months of age
  2. Season:
    • More deaths occur in the winter and fall months
  3. Population
    • Approximately 6,000 babies die of SIDS in the U.S. each year
    • Twenty babies died in Clark Co. in 1998 and 1999
    • Occurs at the rate of 1 per 700 live births
    • 60% male vs. 40% female
    • SIDS affects babies of all races, religions, and ethnic groups
  4. Increased risk or higher rates for:
    • Low birth weight babies, under 2,500 grams or 5-6 pounds
    • Premature babies
    • Babies of mothers who smoke during or after pregnancy
    • Babies of multiple births (twins or triplets)
    • Babies born within 18 months of one another
    • Babies of younger mothers

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II. Overview of Current Theories & Research

A. Triple Risk Model (Instructor note: Show overhead or handout).

  • Critical Development Period (Instructor note: 90% of SIDS deaths occur during the first six months of life, with a peak at 2-4 months. During this Critical Development Period, babies are at an increased risk for SIDS because their bodies are undergoing many changes in their development.)
  •  Vulnerable Infant (Instructor note: Researchers believe SIDS infants may have some sort of subtle defect they are not yet able to detect. These infants are thought to be vulnerable in some way and represented as the Vulnerable Infant, in the Triple Risk Model. Some doctors believe that low birth weight or prematurity may be the only vulnerability factor that needs to be present to increase the risk of SIDS.)
  • Outside Stressors (Instructor note: Combining the other two with an Outside Stressor, or environmental stress/risk factor may “trigger” a SIDS event. This is the only area we can address at this time.)

The Cause(s) of SIDS is Unknown

  • Different things may interact with one another to result in a SIDS death.
  • There are many research theories looking at why SIDS deaths occur.
  • Most research points to a malfunction in the lower part of the brain.

The malfunction in the lower part of the brain may result in an infant’s inability to:

  1. Respond to a lack of oxygen
  2. Respond to elevated levels of carbon dioxide
  3. Control blood pressure
  4. Control heart rate
  5. Regulate body temperature
  6. Keep airways open

Risk Reduction Recommendations

Sleep Position

  • AAP Statement on Sleep Position
  • “Back to Sleep” Campaign

SIDS in Child Care

  • Researchers are concerned that there is an increased risk for SIDS when a baby is traditionally placed on their back to sleep at home and then placed for the first, second or third time on their tummy to sleep in someone else’s care.
  • It is crucial for providers to speak with the parents of babies in their care about the back-sleeping recommendation


  • Bedding becomes especially important as the infant becomes older and starts to choose his or her own sleep position.
  • Avoid placing the baby on soft quilts or comforters, fluffy pillows, waterbeds, or sheepskins. Bumper pads are not recommended if the slats of the crib are no wider than 2 and 3/8 inches. Stuffed animals should not be placed in the crib with the baby.


Do not overbundle or overdress the baby. Dress the baby in one (thin) layer more than you may dress.


Babies of mothers who smoke during pregnancy have a 3 times higher risk of SIDS. Babies exposed to second-hand smoke have a 2 times higher risk of SIDS.


  • Some researchers have found that breastfeeding is a protective factor for SIDS.
  • Prenatal Care and Well-Baby Care

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  • Prenatal care can reduce the chance of the mother having baby too early or a baby that is too small, both of which are risk factors for SIDS.
  • An Upper Respiratory Infection (URI) may be present right before or at the time of death and may serve as a triggering event for a SIDS death. Therefore, it is also important for parents to take babies to the doctor on a regular basis.

Emergency Guidelines For Child Care Providers

  • Start CPR • Notify the Paramedics—Call 911
  • Notify the child’s parents
  • Notify your child care licensing agency
  • Notify Clark County SIDS Community Awareness Alliance 702-455-3894

Death Scene Investigations

  • Law enforcement officials are required to do death scene investigations in all cases of sudden and unexpected deaths
  • The provider can give important information, which will assist the medical examiner in making an accurate diagnosis.
  • These questions are not meant to imply the caregiver has done anything wrong.


Although this can be a “tearful” subject, let’s end on a positive note.

  • 43% decrease in SIDS deaths nationally since 1995
  • Cause of SIDS not known
  • Can respond to SIDS by reducing risk factors
    1. “Back to Sleep” campaign
    2. Bedding
    3. No smoking
    4. Breastfeeding
    5. Control temperature
    6. Prenatal and well-baby check-up
Kock, J. 2004, Sudden Infant Death Syndrome (Sids) In Southern Nevada, Extension | University of Nevada, Reno, CM-04-03

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