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Definition: sudden infant death syndrome from The Macquarie Dictionary
1.

a syndrome leading to death in babies up to about two years old, the mechanisms of which are not yet understood but have been variously linked with excessive heat or cold, respiratory ailments giving rise to difficulty in breathing, the failure of the involuntary breathing process during sleep, and other such possible causes; cot death.


Summary Article: Sudden Infant Death Syndrome (SIDS)
from Health Reference Series: Respiratory Disorders Sourcebook
What Is Sudden Infant Death Syndrome (SIDS)?

1Sudden infant death syndrome (SIDS) is the sudden, unexplained death of a baby younger than 1 year of age that doesn't have a known cause even after a complete investigation. This investigation includes performing a complete autopsy, examining the death scene, and reviewing the clinical history.

When a baby dies, healthcare providers, law enforcement personnel, and communities try to find out why. They ask questions, examine the baby, gather information, and run tests. If they can't find a cause for the death, and if the baby was younger than 1 year old, the medical examiner or coroner will call the death SIDS.

If there is still some uncertainty as to the cause after it is determined to be fully unexplained, then the medical examiner or corner might leave the cause of death as “unknown.”

Fast Facts about SIDS
  • SIDS is the leading cause of death among babies between 1 month and 1 year of age.

  • More than 2,000 babies died of SIDS in 2010, the last year for which such statistics are available.

  • Most SIDS deaths occur when in babies between 1 month and 4 months of age, and the majority (90%) of SIDS deaths occur before a baby reaches 6 months of age. However SIDS deaths can occur anytime during a baby's first year.

  • SIDS is a sudden and silent medical disorder that can happen to an infant who seems healthy.

  • SIDS is sometimes called “crib death” or “cot death” because it is associated with the timeframe when the baby is sleeping. Cribs themselves don't cause SIDS, but the baby's sleep environment can influence sleep-related causes of death.

  • Slightly more boys die of SIDS than do girls.

  • In the past, the number of SIDS deaths seemed to increase during the colder months of the year. But today, the numbers are more evenly spread throughout the calendar year.

  • SIDS rates for the United States have dropped steadily since 1994 in all racial and ethnic groups. Thousands of infant lives have been saved, but some ethnic groups are still at higher risk for SIDS.

SIDS Is Not

SIDS is not the cause of every sudden infant death.

Each year in the United States, thousands of babies die suddenly and unexpectedly. These deaths are called SUID, which stands for “Sudden Unexpected Infant Death.”

SUID includes all unexpected deaths: those without a clear cause, such as SIDS, and those from a known cause, such as suffocation. One-half of all SUID cases are SIDS. Many unexpected infant deaths are accidents, but a disease or something done on purpose can also cause a baby to die suddenly and unexpectedly.

“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 can't breathe. Strangulation is when something presses on or wraps around the baby's neck, blocking the baby's airway. These deaths are not SIDS.

Other things that SIDS is not:

  • SIDS is not the same as suffocation and is not caused by suffocation.

  • SIDS is not caused by vaccines, immunizations, or shots.

  • SIDS is not contagious.

  • SIDS is not the result of neglect or child abuse.

  • SIDS is not caused by cribs.

  • SIDS is not caused by vomiting or choking.

  • SIDS is not completely preventable, but there are ways to reduce the risk.

What Causes SIDS?

We don't know exactly what causes SIDS at this time.

Scientists and healthcare providers are working very hard to find the cause or causes of SIDS. If we know the cause or causes, someday we might be able to prevent SIDS from happening at all.

More and more research evidence suggests that infants who die from SIDS are born with brain abnormalities or defects. These defects are typically found within a network of nerve cells that send signals to other nerve cells. The cells are located in the part of the brain that probably controls breathing, heart rate, blood pressure, temperature, and waking from sleep. At the present time, there is no way to identify babies who have these abnormalities, but researchers are working to develop specific screening tests.

But scientists believe that brain defects alone may not be enough to cause a SIDS death. Evidence suggests that other events must also occur for an infant to die from SIDS. Researchers use the Triple-Risk Model to explain this concept. In this model, all three factors have to occur at the same time for an infant to die from SIDS. Having only one of these factors may not be enough to cause death from SIDS, but when all three combine, the chances of SIDS are high.

Even though the exact cause of SIDS is unknown, there are ways to reduce the risk of SIDS and other sleep-related causes of infant death.

What Do We Know about Risk for SIDS and Other Sleep-Related Causes of Infant Death?

Even though we don't know the exact cause of SIDS, we do know that some things can increase a baby's risk for SIDS and other sleep-related causes of infant death. The good news is that there are ways to reduce the risk.

Known Risk Factors for SIDS and Other Sleep-Related Causes of Infant Death

Babies who usually sleep on their backs but who are then placed to sleep on their stomachs, such as for a nap, are at very high risk for SIDS.

Babies are at higher risk for SIDS if they:

  • Sleep on their stomachs.

  • Sleep on soft surfaces, such as an adult mattress, couch, or chair or under soft coverings.

  • Sleep on or under soft or loose bedding.

  • Get too hot during sleep.

  • Are exposed to cigarette smoke in the womb or in their environment, such as at home, in the car, in the bedroom, or other areas.

  • Sleep in an adult bed with parents, other children, or pets; this situation is especially dangerous if:

    • The adult smokes, has recently had alcohol, or is tired.

    • The baby is covered by a blanket or quilt.

    • The baby sleeps with more than one bed-sharer.

    • The baby is younger than 11 to 14 weeks of age.

Ways to Reduce the Risk of SIDS and Other Sleep-Related Causes of Infant Death

Research shows that there are several ways to reduce the risk of SIDS and other sleep-related causes of infant death:

  • Always place your baby on his or her back to sleep, for naps and at night, to reduce the risk of SIDS.

  • Use a firm sleep surface, such as a mattress in a safety-approved2 crib, covered by a fitted sheet, to reduce the risk of SIDS and other sleep-related causes of infant death.

  • Room sharing—keeping baby's sleep area separate from your sleep area in the same room where you sleep—reduces the risk of SIDS and other sleep-related causes of infant death.

  • Keep soft objects, toys, crib bumpers, and loose bedding out of your baby's sleep area to reduce the risk of SIDS and other sleep-related causes of infant death.

  • To reduce the risk of SIDS, do not smoke during pregnancy, and do not smoke or allow smoking around your baby.

  • Breastfeed your baby to reduce the risk of SIDS.

  • Give your baby a dry pacifier that is not attached to a string for naps and at night to reduce the risk of SIDS.

  • Do not let your baby get too hot during sleep.

  • Follow healthcare provider guidance on your baby's vaccines and regular health checkups.

  • Avoid products that claim to reduce the risk of SIDS and other sleep-related causes of infant death

  • Do not use home heart or breathing monitors to reduce the risk of SIDS.

  • Give your baby plenty of tummy time when he or she is awake and when someone is watching.

1

This chapter includes text excerpted from “What Is SIDS?” Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), October 29, 2015.

2

* Visit the U.S. Consumer Product Safety Commission website for more information about crib safety: www.cpsc.gov / en / Safety-Education / Safety-Education-Centers / cribs

© 2016 Omnigraphics, Inc.

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