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Sudden infant death syndrome (SIDS) is a syndrome marked by the symptoms of sudden and unexplained death of an apparently healthy infant aged one month to one year. The term cot death is often used in the United Kingdom, Australia and New Zealand, while crib death
is used in North America.
Risk factors and statistics
SIDS is responsible for roughly 0.05%, or 50 deaths per 100,000 births in the U.S. It is responsible for far fewer deaths than congenital disorders and disorders related to short gestation, though it is the leading cause of death in healthy babies after one month of age.
Very little is known for sure about the possible causes of SIDS, and there is no proven method for prevention. Although studies have identified risk factors for SIDS, such as putting infants to bed on their stomachs, there has been little understanding of the syndrome's biological cause or causes. The frequency of SIDS appears to be a strong function of infant sex and the age, ethnicity, education, and socio-economic status of the parents.
According to a study published in October 2006 in the Journal of the American Medical Association, babies who die of SIDS have abnormalities in the part of the brain that helps control functions like breathing, blood pressure and arousal. Researchers examined the brains of 31 babies who had died of SIDS and 10 who had died from other causes. They found that abnormalities in the brain stem appear to affect the ability to use and recycle serotonin, which is responsible for regulating mood as well as vital body functions. According to the National Institutes of Health, which funded the study, the new finding is the strongest evidence to date suggesting that innate differences in a specific part of the brain may place some at increased risk of dying from SIDS.
Listed below are several factors associated with increased probability of the syndrome based on information available prior to this recent study.
Article from :http://en.wikipedia.org/wiki/Sudden_infant_death_syndrome#Speculated_associations