1 – What is ‘Sudden Unexpected Death in Infancy’ (SUDI)?

When a previously healthy baby or child dies suddenly and unexpectedly, the terms “Sudden Unexpected Death in Infancy” (often abbreviated to SUDI) or “Sudden Unexpected Death in Childhood” (SUDC), may be used by the medical professionals to explain the death. All SUDI are unexplained at the time the baby or young child dies – no one expected it to happen and no one initially knows what caused the baby or child to die.

It can be helpful to think of SUDI as an umbrella term and one which is used in the first instance.

In time, some SUDI may become explained. This can be at the initial post-mortem or many months after as results come back which may give a reason for the death.

Many SUDI remain unexplained deaths.

The terms ‘cot death’ or ‘SIDS’ are also commonly used, although pathologists in Scotland rarely use the term SIDS.

Sudden Infant Death Syndrome (SIDS) was defined in 1969 as “the sudden death of an infant or young child which is unexpected by history and in which a thorough post mortem examination fails to demonstrate an adequate cause for death”. SIDS is very rarely used to describe the cause of death on death certificates in Scotland. Terms such as “Sudden Unexpected Death in Infancy” and “Unascertained” are now much more likely to be used.

You can read more details explaining what SUDI is on our education website safesleepscotland.org