New clues emerge about possible factors behind sudden infant death syndrome

Sudden infant death syndrome, the unforeseen and unexplained death of a baby younger than one year old, is by definition a mystery. But researchers are getting closer to understanding some of the risk factors and mechanisms that contribute to SIDS.

The prevailing theory points to three possible factors: First, the infant is at a critical stage of development during the first year of life. Second, the baby is exposed to a stressor, such as sleeping face down, which can lower the amount of oxygen in their blood while raising the level of carbon dioxide. And third, the infant has an underlying abnormality that makes it harder to survive that traumatic event.

A study published Thursday in the Journal of Neuropathology & Experimental Neurology points to one such abnormality.

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