Sudden Infant Death Syndrome (SIDS) is the sudden death of an infant younger than 1 year of age that remains unexplained after a thorough case investigation. This investigation includes performing a complete autopsy, examining the death scene, and reviewing the clinical history.
When a baby dies, health care providers, law enforcement personnel, and communities try to find out why. They ask questions, examine the baby, gather information, and run tests. If they can’t find a cause for the death, and if the baby was younger than 1 year old, the medical examiner or coroner will call the death SIDS.
If there is still some uncertainty as to the cause after it is determined to be fully unexplained, then the medical examiner or corner might leave the cause of death as “unknown”.