These factors may include problems with sleep arousal or an inability to sense a build-up of carbon dioxide in the blood. Almost all SIDS deaths occur without any warning or symptoms when the infant is thought to be sleeping.
SIDS is most likely to occur between 2 and 4 months of age, and 90% occur by 6 months of age. It occurs more often in winter months, with the peak in January. There is also a greater rate of SIDS among Native and African Americans.
The following have been linked to an increased risk of SIDS:
- Babies who sleep on their stomachs
- Babies who are around cigarette smoke while in the womb or after being born
- Babies who sleep in the same bed as their parents
- Babies who have soft bedding in the crib
- Multiple birth babies (being a twin, triplet, etc.)
- Premature babies
- Babies who have a brother or sister who had SIDS
- Mothers who smoke or use illegal drugs
- Teen mothers
- Short time period between pregnancies
- Late or no prenatal care
- Situations of poverty
Task Force on Sudden Infant Death Syndrome. The Changing Concept of Sudden Infant Death Syndrome: Diagnostic Coding Shifts, Controversies Regarding the Sleeping Environment, and New Variables to Consider in Reducing Risk. Pediatrics. 2005 Nov;116 (5).
Hauck FR, Omojokun OO, Siadaty MS. Do Pacifiers Reduce the Risk of Sudden Infant Death Syndrome? A Meta-analysis. Pediatrics. 2005 Nov;116 (5).
Hunt CE, Hauck FR. Sudden infant death syndrome. Canadian Medical Association Journal. 2006 Jun;174(13).
Hauck FR, Omojokun OO, Siadaty MS. Do Pacifiers Reduce the Risk of Sudden Infant Death Syndrome? A Meta-analysis. Pediatrics. 2005 Nov;116 (5).
Hunt CE, Hauck FR. Sudden infant death syndrome. Canadian Medical Association Journal. 2006 Jun;174(13).