The National Institute of Child Health and Human Development (NICHD) convened an expert panel in 1991 to determine criteria for defining the Sudden Infant Death Syndrome (SIDS). This participants were from multiple university and medical examiner offices in the United States.


Definition of SIDS:

(1) infant age less than 365 days old

(2) no cause of death identified at autopsy

(3) toxicology and metabolic screening tests negative

(4) medical history of the infant and mother negative

(5) no cause of death found at the death scene


If no definite cause of death was found but the infant did not meet the criteria for SIDS, then the case should be designated "unresolved" or "undetermined". This includes cases where:

(1) The infant had vomiting or diarrhea in the 24 hours prior to death but for which no infectious agents was identified.

(2) Suspicion of child abuse, neglect, etc. where insufficient evidence if available.

(3) History of maternal drug abuse or other behavior that may be contributory.



(1) Sudden unexplained death for neonates < 7 days of age should be included as SIDS if other criteria are met.

(2) Infants with health problems prior to death are not excluded from SIDS. Not all SIDS infants are perfectly healthy prior to death.

(3) A thorough examination is required before the diagnosis of SIDS can be made. This includes a complete post-mortem examination.

(4) A death scene investigation is critical to rule out accidental, environmental and unnatural mechanisms of death.

(5) All of the information is required in order to properly counsel the parents about current and future children.


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