Health Information and Tools >  Sudden Infant Death Syndrome (SIDS)

Main Content

Sudden Infant Death Syndrome (SIDS)

Condition Basics

What is sudden infant death syndrome (SIDS)?

Sometimes a baby who seems healthy dies during sleep. If this happens to a healthy baby younger than 1 year old, it's called sudden infant death syndrome or SIDS.

In most cases, a parent or caregiver places the baby down to sleep and returns later to find the baby has died. It's no one's fault. SIDS can happen even when you do everything right.

What causes it?

Doctors don't know what causes SIDS, but researchers are studying the possibility that SIDS may be caused by problems with how well the brain controls breathing, heart rate and rhythm, and temperature during the first few months of life.

There are some factors that may increase the risk of SIDS.

If during pregnancy, the mother:

  • Is younger than 20 years old.
  • Smokes or vapes.
  • Uses drugs or alcohol.
  • Has not had prenatal care.

If the baby is:

  • Premature.
  • Part of a multiple pregnancy (for example, a twin or triplet).
  • Put down to bed on their stomach or side.
  • In a bed on a soft surface or with loose blankets or pillows.
  • Sharing a bed with parents, siblings, or pets.
  • Dressed too warmly or in a very warm room.

What are the symptoms?

SIDS has no symptoms or warning signs. Babies who die of SIDS seem healthy before being put to bed. They show no signs of struggle and are often found in the same position as when they were placed in the bed.

How is it diagnosed?

SIDS is named the cause of death only when no other cause is found. To find out why a baby died, medical experts review the baby's and parents' medical histories, study the area where the baby died, and do an autopsy.

How can you reduce the risk of SIDS?

There is no sure way to prevent SIDS. But there are some things you can do to help reduce the risk of SIDS and other sleep-related deaths.

  • Put your baby on their back to sleep, every sleep.
  • Use a crib, cradle or bassinet with a firm, flat surface that is free of clutter.
  • Keep your baby warm, not hot.
  • Share a room with your baby. Room-sharing is recommended for the first 6 months.
  • Don’t share a bed, sofa or any other sleep surface with your baby. Sharing a bed or sleep surface with your baby has risks and is not recommended.
  • Keep spaces smoke-free before and after birth.
  • Breastfeed your baby.

For more information about SIDS, visit Safe Sleep for Baby's First Year.

How can a family cope after losing a baby to SIDS?

Each member of your family may respond to the loss of the baby in a different way. These different ways of coping with the baby's death can strain a marriage and a family. Along with feeling grief, family members may be struggling with feelings of guilt. Support from family, friends, your doctor, and possibly other health professionals is very important for everyone. You might find it helpful to:

  • Join a grief support group. Ask your doctor if one for parents who have lost babies to SIDS is available in your area.
  • Get help from a counsellor, a psychologist, or a psychiatrist. Many families benefit from group counselling to help them deal with the tensions that arise after the loss of a baby.
  • Talk with a close family member, a friend, or a spiritual adviser.

Credits

Adaptation Date: 11/23/2023

Adapted By: Alberta Health Services

Adaptation Reviewed By: Alberta Health Services

Adapted with permission from copyrighted materials from Healthwise, Incorporated (Healthwise). This information does not replace the advice of a doctor. Healthwise disclaims any warranty and is not responsible or liable for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.