Safe sleeping and sudden unexpected infant death

How do I make my baby’s sleep safe?

For older babies, the rate of sudden unexpected infant death has fallen since 1994 in the U.S.A., when health-care providers began to recommend placing babies on their backs to sleep. But for babies under one month of age, the rate has remained steady. Many of these deaths have been blamed on unsafe sleeping habits. To minimize the risk of sudden unexpected death, babies should be placed on their back on a firm surface and soft objects, and loose bedding are kept away from the baby’s sleep area. Mothers should avoid smoke exposure, alcohol, and illicit drugs. The crib should meet modern safety standards and each crib should only hold one baby. Parents should have a close look at the place where the baby sleeps and make sure it is safe.

A) Describing sudden unexpected infant death and sudden infant death syndrome

The term sudden unexpected infant death (SUID) is a broad term that describes all sudden infant deaths including those from accidental death such as strangulation, medical causes, sudden infant death syndrome (SIDS), and homicide. SIDS is one possible reason for SUID.

SUID is the most common cause of death among babies between the ages of one month and one year. In the U.S.A., since 1994, when recommendations to place sleeping babies on their backs were created, the rate of sudden unexpected infant death has decreased in babies older than one month. The rate for babies under one month has remained steady, and an increasing number of these deaths have been blamed on unsafe sleeping habits (Bass 2018).

B) Causes of SUID

SUID may be caused by:

1) Unsafe habits that may result in (Erck Lambert 2019; Parks 2021):

  • Suffocation caused by soft bedding.
  • Sleeping on the stomach instead of the back.
  • Entrapment (being trapped between two objects such as a mattress and a wall).
  • Choking on something the baby has taken into the mouth.
  • Being laid on by a parent.
  • SIDS.

2) SUID may also be caused by:

  • Infection.
  • Heart abnormalities.
  • Abnormalities of salt (electrolyte) levels in the blood.
  • Starvation and dehydration.
  • Poisoning.
  • Genetic conditions (such as heart or metabolic disorders) (Männikkö 2018; Rubens 2013).
  • Trauma.

C) Keeping babies safe

There are a number of ways to lower the risk of SUID. There are additional conditions if you are bed-sharing.

National guidelines for safe sleeping vary. Some of the American Academy of Pediatrics recommendations are that mothers (Moon 2016):

  • Get regular prenatal care while pregnant.
  • Avoid smoke exposure during pregnancy and after birth.
  • Avoid alcohol and drug abuse during pregnancy and after birth.
  • Avoid overheating the baby.
  • Breastfeed to reduce the risk of SIDS.
  • Place the baby on the back for sleeping.
  • Use a firm sleep surface.
  • Room-share and keep the baby on a separate sleep surface.
  • Keep soft objects, such as pillows, stuffed animals, and bumper pads, and loose bedding away from the baby’s sleep area.
  • Not use machines to monitor the baby’s breathing and heart rate at home (cardiorespiratory monitors) as a strategy to reduce the risk of SIDS.

Babies need a safe place to sleep. The following practices are unsafe and should be avoided:

  • Having more than one baby in a crib.
  • Using old or broken cribs or cribs that do not meet modern safety standards.
  • Using an improperly assembled crib.
  • Sleeping on couches, armchairs, rockers, sofa, recliners, waterbeds, or other soft surfaces.
  • Sleeping in car seats.
  • Sleeping on an inclined surface.
  • Using an unsafe baby carrier.

Babies can get into trouble very quickly. Have a thorough look at the place where your baby sleeps and make sure it is safe. For more information, please discuss this with your health-care providers.


Bass JL, Gartley T, Lyczkowski DA, et al. Trends in the Incidence of Sudden Unexpected Infant Death in the Newborn: 1995-2014. J Pediatr. 2018 Feb 5. pii: S0022-3476(17)31740-7
Erck Lambert AB, Parks SE, Cottengim C, et al. Sleep-Related Infant Suffocation Deaths Attributable to Soft Bedding, Overlay, and Wedging. Pediatrics. 2019 May;143(5). pii: e20183408
Männikkö R, Wong L, Tester DJ, et al. Dysfunction of NaV1.4, a skeletal muscle voltage-gated sodium channel, in sudden infant death syndrome: a case-control study. Lancet. 2018 Mar 28. pii: S0140-6736(18)30021-7
Moon RY; Task Force On Sudden Infant Death Syndrome. SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment. Pediatrics. 2016 Nov;138(5). pii: e20162940

Parks SE, Erck Lambert AB, et al. Explaining Sudden Unexpected Infant Deaths, 2011-2017. Pediatrics. 2021 May;147(5):e2020035873 

Rubens D, Sarnat HB. Sudden infant death syndrome: an update and new perspectives of etiology. Handb Clin Neurol. 2013;112:867-74