Sudden Unexpected Infant Deaths

Sudden unexpected infant death (SUID) is the death of an infant less than one year of age that occurs suddenly and unexpectedly, and whose cause of death is not immediately known.

Although similar, SUID is not Sudden Infant Death Syndrome (SIDS). SUID is an umbrella term and encompasses many types of infant deaths. After a full investigation and autopsy, these deaths may be determined to be the result of accidental suffocation, entrapment, a medical problem, an accident or trauma, or SIDS.

Most SUIDs are reported as a sleep-related infant death, including:

  • Sudden Infant Death Syndrome (SIDS). SIDS is the sudden, unexpected death of an infant under one year of age which remains unexplained after a complete investigation, including: an autopsy; examination of death scene; and review of medical history.
  • Accidental Suffocation and Strangulation in Bed (ASSB). ASSB can occur due to soft bedding, overlay (when another person rolls on top or against the infant); wedging or entrapment (when an infant is wedged between the mattress and the wall or bed frame); or strangulation (when something is wrapped around the infant’s neck, blocking the airway).
  • Undetermined. Some infant deaths are classified as “Undetermined” because either one or more parts of the investigation were not conducted, or sufficient evidence after the investigation is not available.