Sudden infant death syndrome (SIDS), also known as cot death or crib death is one of parents’ greatest fears. Learn how to reduce the risk of SIDS and other sleep-related infant deaths.

What is SIDS? 

SIDS is the death of an apparently healthy baby that remains unexplained after a thorough autopsy. Although researchers believe SIDS probably has more than one cause, they remain uncertain about what SIDS is or what causes it. 

It is known that SIDS is not caused by...

  • suffocation
  • choking
  • vomiting

Who is affected by SIDS?

Although SIDS can occur anytime up until the age of 2 years, the peak incidence occurs between the ages of 2 and 4 months. Approximately 90% of cases occur in babies younger than 6 months.  Babies are considered at risk for SIDS up to the age of 1 year.


Up until the last 10 years or so, there was little research done into SIDS. Research has been able to identify risk factors and recommend ways parents can reduce the risk of SIDS. 

As more parents begin to follow SIDS recommendations, the number of deaths from SIDS has continued to slowly drop. In many countries where these recommendations are followed the incidence of SIDS has dropped by over 50% to 70%. (See International SIDS statistics.)

How can SIDS be prevented? 

Sadly SIDS can not be predicted, prevented or reversed, but there are many things you can do to reduce the risk of SIDS. Research into SIDS has lead to the following recommendations. 

1. Place your baby on his/her back to sleep

This is one of the most important things you can do to help protect your baby. Sleeping babies on their stomachs does not cause SIDS but has been linked with an increased risk of SIDS. Babies sleeping on their stomachs are approx. 12 times the same risk as babies who sleep on their backs.

Although babies who are placed on their sides to sleep have a lower risk of SIDS than those placed on their stomachs, the back sleeping position is the best position for babies from 1 month to 1 year. Babies positioned on their sides to sleep should be placed with their lower arm forward to help prevent them from rolling onto their stomach.

2. Maintain a smoke-free environment

Avoid exposing your baby to tobacco smoke. Don't have your baby in the same house or car with someone who is smoking. The greater the exposure to tobacco smoke, the greater the risk of SIDS.

3. Avoid overheating

Don't overdress your baby, which may allow him/her to get too warm. Cover him/her with only the amount of bed clothing that you feel you would be comfortable with if you were sleeping. Better still dress him so that he doesn't need covers when he sleeps. Don't heat his room more than your own. Don't cover your baby's head with a hat or bonnet while he/she is sleeping. 

4. Sleep your baby on a firm surface

Make sure your baby sleeps on a firm clean well-fitted mattress or other firm surface. Never put your baby down to sleep on a waterbed or a beanbag. Avoid using other soft surfaces, such as pillows, bumper, quilts, comforters or sheepskins.

To stop your baby from wriggling under the covers while sleeping, position your baby so his/her feet are touching the bottom of the crib. Tuck in bed clothing securely so that it can't be accidentally pulled over his/her head. 

5. Avoid exposing your baby to people with respiratory infections

The incidence of SIDS is greater in winter months. SIDS often occurs in association with relatively minor respiratory and gastrointestinal infections. Avoid crowded places. Carefully clean anything that comes in contact with your baby. Have people wash their hands before holding or playing with your baby.

6. Breastfeed your baby as long as possible

Studies have shown that breastfed babies have a lower SIDS rate than formula fed babies do. Breast milk decreases the risk of your baby developing respiratory infections (colds or flu) as well gastro-intestinal infections (vomiting and diarrhea).

Risk of SIDS and co-sleeping

Recently, scientific studies have demonstrated that co-sleeping between mother and baby, can alter sleep patterns of the mother and baby. These studies have led to speculation that co-sleeping may reduce the risk of SIDS. However, there are no scientific studies demonstrating that sharing a bed with a baby reduces the risk of SIDS. Some studies actually suggest that co-sleeping, under certain conditions, may in fact increase the risk of SIDS. 

It is important to be aware that adult beds, unlike cribs, are not designed to meet safety standards for babies. Co-sleeping may carry additional risks to a small baby of accidental entrapment and suffocation. There are some reports of babies being suffocated by overlying by an adult, particularly when the adult is in an unnaturally depressed state of consciousness, such as from alcohol or mind-altering drugs. Adults (other than parents), other children including siblings should avoid sharing a bed with a baby.

If you choose to co-sleep with your baby, it is important that any adult sharing the bed should avoid smoking, drinking and using illicit drugs. Ensure your mattress is firm. Care should be taken to avoid using soft sleep surfaces. Quilts, blankets, pillows, comforters, or other soft materials should not be placed under your baby. Care needs to be taken to make sure your baby's head does not become covered by the bed clothing. 

Will my baby choke sleeping on their back?

Previous generations of parents were advised to sleep babies on their tummies. At the time this was justified by a fear that babies who slept on their backs could vomit and choke. However, recent research has proven this fear as unfounded. Studies in countries where there has been a switch from babies sleeping on their stomachs to sleeping on their backs have not found any evidence of increased risk of choking OR other problems.

Where to find more information about SIDS

There are a number of great web sites with information about SIDS. Here are a few... 

American SIDS Institute
SIDS and Kids Online
National SIDS/Infant Death Resource Center
The Canadian Foundation for the Study of Infant Death
The Foundation for the Study of Infant Deaths - UK

 Written by Rowena Bennett - copyright 2022 - All rights reserved.