Infant Sleep

Safe Infant Sleep

Infant sleep-related deaths are the leading cause of death for Utah infants ages one month to one year of age. The majority of these deaths occur in an unsafe sleep environment.

Infant sleep deaths are classified into one of four categories:

  • Sudden Infant Death Syndrome or SIDS
  • SIDS vs. Asphyxia deaths
  • Unintentional injury deaths during sleep
  • Other infant sleep deaths of undetermined manner

"The safest place for a baby to sleep is in the same room as the parents or caregivers but not on the same sleep surface."

Sudden Infant Death Syndrome (SIDS)

In Utah, the largest number of infant sleep-related deaths are from Sudden Infant Death Syndrome (SIDS). SIDS, sometimes called crib death, is the sudden and unexplained death of an infant under one year of age, even after a thorough case investigation. Approximately 80% of all infants who died of SIDS in Utah from 2005-2007 were sleeping in an environment considered unsafe by the American Academy of Pediatrics. Boys are more at risk for SIDS than girls. Studies also show that infants under 12 weeks of age are at greater risk for SIDS while sharing a sleep surface than are infants older than 12 weeks of age (2,3). In Utah, nearly 70% of the infants who died from SIDS from 2005-2007 were under 12 weeks of age and were sharing a sleep surface at the time of their death. SIDS is more prevalent during the winter months (1). It’s thought that the use of extra blankets or clothing may be an added risk factor.

SIDS vs. Asphyxia Deaths

Sometimes circumstances are such that the medical examiner can narrow the source of an infant death down to one of two causes—SIDS or asphyxia—but there is insufficient evidence to determine which was the true cause of death. In these cases, the cause of death will be “undetermined (SIDS vs. Asphyxia).” Asphyxiation can be caused by the position of the infant’s body preventing him or her from breathing adequately. Blankets, pillows, and stuffed toy animals in the sleep environment can also be contributing factors. Nearly 65% of infants who died from SIDS vs. Asphyxia in Utah from 2005-2007 had been sharing a sleep surface with another person, such as a parent or sibling. Hispanic infants were also at a higher risk of dying from these deaths.

Other Infant Sleep Deaths of Undetermined Manner

Most of the infant sleep deaths of undetermined manner involved suspicious circumstances, such as a known drug use by the parents, the discovery of unexplained injuries upon autopsy, a history of child abuse by the parents, the previous death of a child in the home under the same circumstances, or inconsistent parental accounts of the events around the time of death. Many of these deaths also involved co-sleeping.

Risk Factors for Infant Sleep Deaths

There are several risk factors that can place infants at risk of sleep-related deaths. Two of the most common factors associated with infant sleep-related deaths are:

  • The baby being put down to sleep on an adult bed
  • The practice of unsafe co-sleeping

Co-sleeping or Bed Sharing

Co-sleeping is when an infant shares a bed or sleep surface with another person, such as a parent or sibling. From 2005-2007, a total of 51 Utah infants died while sharing a sleep surface.

The safest place for a baby to sleep is in the same room as the parents or caregivers but not on the same sleep surface. A co-sleeper (e.g., Pack-n-Play) or bassinette next to the mother’s bed allows for frequent feedings and is the safest place for a baby.

Placing an Infant on an Adult Bed

Adult beds present several risks to infants. First, for the infant capable of rolling (or squirming), there is no rail to protect him/her from either falling off the mattress or becoming wedged between the mattress and a wall or piece of furniture. Each year, several Utah infants die from becoming wedged between a mattress and a wall or other object. Although less common, fall injuries have resulted in suffocation deaths too. A second risk with adult beds is that they often have softer coverings (e.g., pillow top and memory foam). Young babies may have difficulty moving to get sufficient air if they are placed on their stomachs on these soft sleeping surfaces. Third, an infant can become covered by a pillow or tangled in covers.

Bedding Materials or Items in Cribs

The American Academy of Pediatrics recommends that a crib have a well-fitting mattress with a fitted sheet. Other than the baby, nothing else should be in the crib. A blanket sleeper can be used instead of extra covers or blankets. Each year, several Utah infants die because of inappropriate objects, bedding materials, pillows, or stuffed toy animals being in the crib. Infants can also die as the result of their head becoming wedged between an ill-fitting mattress and crib rails.

Back to Sleep

Since 1994, the National Institute of Child Health and Human Development and the American Academy of Pediatrics have recommended that all healthy babies be placed on their backs to sleep in order to prevent SIDS and other sleep-related deaths. Since then, SIDS rates have declined by more than 50% (3).

Smoking during Pregnancy

Nicotine is thought to impact the development of areas of the brain that regulate breathing. Nationally, infants born to mothers who smoked during pregnancy were 2-5 times more likely to die of SIDS than babies whose mothers did not smoke during pregnancy (5). In Utah, data from the Child Fatality Review Committee showed that infants born to mothers who smoked were three times more likely to die from SIDS and nine times more likely to die from SIDS vs. Asphyxia than infants born to mothers who did not smoke during pregnancy.

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  1. NIH NEWS, National Institutes of Health, “NICHD Alerts Parents to Winter SIDS Risk and Updated AAP Recommendations”; January 18, 2006.
  2. P.S. Bair, P.J. Flemming, I.J. Smith, et al., “Babies sleeping with parents; case-control study of factors influencing the risk of sudden infant death syndrome”, British Medical Journal. 1999; 319:1457-1461.
  3. C. McGarvey, M. McDonnell, A. Chong, M. O’Regan, T. Matthews, “Factors relating to the infant’s last sleep environment in sudden infant death syndrome in the Republic of Ireland”; Archives of Disease in Childhood. 2003; 88:1058-1064.
  4. SIDS Rate Source: CDC, National Center for Health Statistics, Sleep Position Data: NICHD, National Infant Sleep Position Study.
  5. Sawnani, H; Olsen, E; Simakajorboon, N; “The Effect of In Utero Cigarette Smoke Exposure on Development of Respiratory Control: A Review”; Pediatric Allergy, Immunology, and Pulmonology; Volume 23, Number 3, 2010.