SIDS (Sudden Infant Death Syndrome)

What is SIDS?

SIDS (Sudden Infant Death Syndrome) is the diagnosis given for the sudden death of an infant under one year of age for which there is no other cause determined. Because most cases of SIDS occur when a baby is sleeping in a crib, SIDS is commonly known as "crib death." Even though SIDS is the leading cause of death in infants between one month and one year of age, SIDS is a rare event. Only 1.22 of 1000 infants die of SIDS per year.

What causes SIDS?

No one knows the exact cause of SIDS, but there are many theories. Some medical evidence suggests that some SIDS babies are born with brain abnormalities that make them more vulnerable to death during infancy. Such brain abnormalities may be due to a prenatal exposure to a toxic substance or lack of sufficient oxygen. The risk of SIDS may be increased by events occurring after birth, such as lack of oxygen, exposure to high levels of carbon dioxide, or overheating. Infants can have periods of absent breathing for up to twenty seconds, which is normal. They should not turn blue, however, during this period.

What does not cause SIDS?

  • SIDS is not caused by vomiting and choking
  • SIDS is not caused by vaccines or immunizations
  • SIDS is not contagious
  • SIDS is not caused by child abuse

What are the risk factors?

  • Babies who sleep on their stomachs are more likely to die of SIDS than children who sleep on their backs
  • Mothers who smoke during pregnancy are three times more likely to have a SIDS baby
  • Exposure to secondhand smoke doubles the risk of SIDS

How can I lower the risk of SIDS?

There is currently no way of predicting which newborns will be SIDS victims. There are a few measures providers can take, however, to lower the risk of a child dying from SIDS.

  • Keep babies in a smoke-free environment.
  • Babies should be put to sleep on their backs, as opposed to on their stomachs. Studies have shown that placing babies on their backs to sleep has reduced the number of SIDS cases by as much as half.
  • Make sure infants sleep on firm mattresses. Avoid using fluffy blankets or coverings and pillows, sheepskins, blankets, or comforters under an infant.
  • Babies should be warm, but not too warm. An overheated baby is more likely to go into a deep sleep from which the baby is difficult to arouse. The temperature in an infant's room should feel comfortable to you.

Warning Signs — Call a physician immediately if:

  • A baby is listless or unresponsive.
  • A baby stops breathing and turns blue or limp.
  • You have any questions or concerns, or are unsure whether a baby's symptoms are worrisome.

Page last updated: Aug 26, 2013