What Is SIDS?
Sudden infant death syndrome (SIDS) is the sudden and unexplained death of a baby
younger than 1 year old. Most SIDS deaths are associated with sleep, which is why
it's sometimes still called "crib death."
Can SIDS Be Prevented?
A lack of answers is part of what makes SIDS so frightening. SIDS is the leading
cause of death among infants 1 month to 1 year old, and remains unpredictable despite
years of research.
Even so, the risk of SIDS can be greatly reduced. Most important: babies
younger than 1 year old should be placed on their backs to sleep —
never facedown on their stomachs or on their sides. Sleeping on the stomach or side
increases the risk for SIDS.
Who Is at Risk for SIDS?
When considering which babies could be most at risk, no single thing is likely
to cause a SIDS death. Rather, several risk factors might combine to cause an at-risk
infant to die of SIDS.
Most SIDS deaths happen in babies 2 to 4 months old, and cases rise during cold
weather. Black and Native American infants are more likely to die of SIDS than Caucasian
infants. More boys than girls fall victim to SIDS.
Other possible risks include:
Doctors diagnose most health problems based on the symptoms they cause. But most
SIDS diagnoses come only after all other possible causes of death have been ruled
out. This review helps tell true SIDS deaths from those due to accidents, abuse, and
previously undiagnosed conditions, such as cardiac or metabolic disorders.
Why Is Stomach Sleeping Dangerous?
SIDS is more likely among babies placed on their stomachs to sleep than among those
sleeping on their backs. Babies also should not be placed on their sides to sleep.
A baby can easily roll from a side position onto the belly during sleep.
Some researchers believe that stomach sleeping may block the airway and hurt breathing.
Stomach sleeping can increase "rebreathing" — when a baby breathes in his or
her own exhaled air — particularly if the infant is sleeping on a soft mattress
or with bedding, stuffed toys, or a pillow near the face. As the baby rebreathes exhaled
air, the oxygen level in the body drops and the level of carbon dioxide rises.
Infants who die from SIDS may have a problem with the part of the brain that helps
control breathing and waking during sleep. If a baby is breathing stale air and not
getting enough oxygen, the brain usually triggers the baby to wake up and cry to get
more oxygen. If the brain is not picking up this signal, oxygen levels will continue
to fall.