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.
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
What Is "Back to Sleep"?
In response to evidence that stomach sleeping might contribute to SIDS, the American
Academy of Pediatrics (AAP) created its "Back to Sleep" campaign, which recommended
that all healthy infants younger than 1 year of age be placed on their backs to sleep.
Babies should be placed on their backs until 12 months of age. Older infants may
not stay on their backs all night long, and that's OK. Once babies consistently roll
over from front to back and back to front, it's fine for them to be in the sleep position
they choose. There's no need to use positioners, wedges, and other devices that
claim to reduce the risk of SIDS.
Some parents might worry about "flat
head syndrome" (positional plagiocephaly). This is when babies develop a flat
spot on the back of their heads from spending too much time lying on their backs.
Since the "Back to Sleep" campaign, this has become more common — but is easily
treatable by changing a baby's position in the crib and allowing for more supervised
"tummy time" while he or she is awake.
Many parents fear that babies put to sleep on their backs could choke on spit-up
or vomit. However, only babies with certain uncommon upper airway malformations may
need to sleep on their stomachs. There's no increased risk of choking for healthy
infants and most infants with gastroesophageal
reflux (GER) who sleep on their backs.
Parents should talk to their child's doctor if they have questions about the best
sleeping position for their baby.
What Is "Safe to Sleep"?
Since the AAP's recommendation, the rate of SIDS has dropped greatly. Still, SIDS
remains the leading cause of death in young infants. The "Safe to Sleep" campaign
builds on "Back to Sleep," reminding parents and caregivers to put infants to sleep
on their backs and provide a safe sleep environment.
Here's how parents can help reduce the risk of SIDS and other sleep-related deaths:
Get early and regular prenatal care.
Place your baby on a firm mattress to sleep, never on a pillow, waterbed, sheepskin,
couch, chair, or other soft surface.
Cover the mattress with a fitted sheet and no other bedding. Keep soft objects
and loose bedding out of the sleep area.
Practice room-sharing without bed-sharing.
Experts recommend that infants sleep in their parents' room — but on a separate
surface, like a bassinet or crib next to the bed — until the child's first birthday,
or for at least 6 months, when the risk of SIDS is highest.
Breastfeed, if possible.
Exclusive breastfeeding or feeding with expressed milk is most protective, but any
breastfeeding has been shown to reduce the risk of SIDS.
Put your baby to sleep with a pacifier during the first year of life. If your
baby rejects the pacifier, don't force it. If the pacifier falls out during sleep
you don't have to replace it. If you're breastfeeding, wait until breastfeeding is
Make sure your baby does not get too warm while sleeping. Dress your infant for
the room temperature, and don't overbundle. Watch for signs of overheating, such as
sweating or feeling hot to the touch.
Don't smoke during pregnancy
or after birth. Infants of moms who smoked during pregnancy are more at risk for SIDS
than those whose mothers were smoke-free; exposure to secondhand smoke also raises
a baby's risk, and that risk is very high if a parent who smokes shares the bed with
Do not use alcohol or drugs
during pregnancy or after birth. Parents who drink or use drugs should not share a
bed with their infant.
Make sure your baby gets all recommended immunizations.
Studies have shown that babies who receive their vaccines have a 50% lower risk of
For parents and families who have experienced a SIDS death, many groups, including
First Candle, can provide grief counseling, support, and referrals.