About sudden unexpected death in infancy (SUDI)
When babies under one year die unexpectedly in their sleep, it’s often described as sudden unexpected death in infancy (SUDI).
When these deaths are investigated, they’re often found to be one of the following:
- Fatal sleeping accidents: these deaths happen when babies suffocate or get trapped or strangled by things in their sleeping environments.
- Sudden infant death syndrome or SIDS: this is when investigations can’t find a cause of death.
Sometimes SUDI can be explained by a serious illness or a medical condition that the baby was born with.
SUDI is rare and accounts for around 3 deaths in every 10 000 births in Australia.
SUDI including SIDS and fatal sleeping accidents: risks
We don’t know exactly what causes sudden unexpected death in infancy (SUDI) including SIDS and fatal sleeping accidents.
We do know that all babies are at general risk of SUDI including SIDS and fatal sleeping accidents.
This general risk increases when babies:
- have extra underlying risk factors
- are young
- have unsafe sleep environments.
Extra underlying risk factors
Some babies have an underlying risk of SUDI including SIDS and fatal sleeping accidents.
Sometimes these risk factors are things like a heart condition or the way a baby wakes and sleeps.
And sometimes these risk factors are things like babies being:
- exposed to tobacco smoke or drugs before they’re born
- born prematurely
- small when they’re born.
The risk of SUDI including SIDS and fatal sleeping accidents is greatest at 2-4 months, although the risk is there for the first 12 months.
Unsafe sleep environment
Babies’ sleep environments can increase their risk of SUDI including SIDS and fatal sleeping accidents. The sleep environment includes how and where babies are put to sleep and other things happening around babies. These other things might include overheating and being exposed to tobacco smoke.
You can’t usually control extra underlying risk factors like a heart condition. And you can’t change your baby’s age, so you can’t control this type of risk either. But you can reduce the overall risk of SUDI including SIDS and fatal sleeping accidents by following safe sleeping guidelines.
Reducing SUDI and fatal sleeping accident risk with safe sleep environments
Babies’ sleep environments include:
- how babies sleep
- where babies sleep
- what’s around babies when they sleep and at other times.
These sleep environments have many risks for SUDI including SIDS and fatal sleeping accidents. These are risks you can avoid.
Here are risks associated with how babies sleep. You should avoid:
- sleeping babies on their tummies or sides
- sleeping babies with faces or heads covered
- letting babies get overheated – for example, by wearing too many clothes or hats or beanies to sleep.
Here are risks associated with where babies sleep. You should avoid:
- sleeping babies on soft surfaces (like soft mattresses or waterbeds) or on sofas, with or without a parent
- sleeping babies in cots that don’t meet Australian/NZ Standard AS/NZS 2172:2003
- sleeping babies where they could get trapped between mattress and cot, or between bed and wall.
Here are risks associated with what’s around babies. You should avoid:
- exposing babies to tobacco smoke
- sleeping babies with loose or fluffy bedding (like sheepskin or lamb’s wool), or with pillows, soft toys or cot bumpers
- sleeping babies near things that could strangle them, like straps or cords from prams, car seats or blinds.
To learn how to avoid these risks, see our illustrated guide to reducing the risk of SUDI and SIDS. Choosing safe baby furniture, including cots, can help you avoid some of these risks too. And if you’re concerned about your baby’s health, see your child and family health nurse or GP.
Effects of SUDI including SIDS and fatal sleeping accidents
The sudden or unexpected death of a baby is one of the most difficult and devastating experiences that parents will ever face. They often feel anger, guilt, frustration and, above all, grief.
Parents often go over every moment in the last few hours or days of their child’s life, searching for clues. They might wonder whether their baby might still be alive if they’d done things a little differently. They might feel guilty they didn’t check on their baby one last time before going to sleep themselves, or that they didn’t wake their baby for a midnight feed.
When a child dies from SUDI including SIDS and fatal sleeping accidents, it can affect not only parents, but also brothers, sisters, grandparents, family members and friends.
There are support services available to parents and families at this difficult time.