How Common is SIDS

Sudden Infant Death Syndrome (SIDS) is the sudden and unexpected death of an infant less than 1 year of age from an unknown cause. SIDS is unpredictable and affects seemingly healthy babies. SIDS is sometimes called crib death. This is because the death may happen when the baby is sleeping in a crib. SIDS is one of the leading causes of death in babies from ages 1 month to 1 year. It happens most often between 2 and 4 months old. SIDS and other types of sleep-related infant deaths have similar risk factors.


Although the cause is unknown, it appears that SIDS might be associated with defects in the portion of an infant’s brain that controls breathing and arousal from sleep. Researchers have identified measures you can take to help protect your child from SIDS. Perhaps the most important is placing your baby on his or her back to sleep.

SIDS in babies happens in families of all social, economic and ethnic groups. SIDS is not contagious, predictable or preventable. SIDS is sudden and silent, occurring most often during sleep, with no signs of suffering.


Risk Factors related to SIDS

  • SIDS in babies is a mysterious syndrome as the cause cannot be determined. But certain risk factors do exist. Some babies are more at risk than others. SIDS is more likely to affect a baby who is between 1 and 4 months old, it is more common in boys than girls, and most deaths occur during the fall, winter and early spring months. Factors that may place a baby at higher risk of dying from SIDS include:
  • babies who sleep on their stomach or their side rather than their back
  • overheating while sleeping
  • too soft a sleeping surface, with fluffy blankets or toys
  • mothers who smoke during pregnancy
  • exposure to passive smoke from smoking by mothers, fathers and others in the household
  • mothers who are younger than 20 years old at the time of their first pregnancy
  • babies born to mothers who had little, late or no prenatal care
  • premature or low birth weight babies
  • having a sibling who died of SIDS