Page "Sudden infant death syndrome" Paragraph 28

According to a 2006 study in the Journal of the American Medical Association ( JAMA ), some babies who die of SIDS have abnormalities in the brain stem ( medulla oblongata ) of underdeveloped serotonin receptors ( which help control functions like breathing, blood pressure and arousal ) and abnormalities in serotonin signaling.

According to the National Institutes of Health, this finding was the strongest evidence at that time that structural differences in a specific part of the brain may contribute to the risk of SIDS.

This abnormality can continue postpartum until the end of the baby's first year, possibly accounting for the increased SIDS risk in premature infants and declining risk in children over 12 months of age.

The authors noted that males have fewer serotonin receptors than females, perhaps contributing to the greater frequency of SIDS in males, but their follow-up 2010 paper failed to reconfirm that gender difference.