Dangers of Stomach Sleeping


Dangers of infants sleeping on their stomachs and Sudden Infant Death Syndrome


When a baby dies, not knowing the cause of death compounds the tragedy for parents.


Sudden infant death syndrome (SIDS) is the term used when an infant dies suddenly of unexplained causes before age 1. In developed countries, SIDS (also known as crib death), is the most common form of death for infants between 1 month and 1 year old.


Although a variety of medical research has suggested biological or environmental risk factors for the syndrome, there is no definitive information about the exact cause. Numerous studies throughout the world have indicated that babies placed to sleep on their stomachs (known as the prone position) are at an increased risk for SIDS. Although the predominant sleep position of infants varies from country to country, most US babies in the early 1990’s were placed on their stomachs to sleep. Since then, the United States has joined a number of other countries in trying to encourage parents to place healthy babies on their backs to sleep.


Three new research studies suggest that the message is getting out but much still needs to be done. One study from the National Institute of Child Health and Human Development found that the proportion of US babies being placed on their stomachs to sleep declined from 70% in 1992 to 24% in 1996. During the same period, there was an approximately 38% decline in SIDS. A second study from the NICHD showed that low-income African-American mothers were more likely to place their babies on their stomachs to sleep. The researchers determined that 93% of mothers who observed their infants placed in the prone position in the hospital after delivery placed their infants in the same position at home.


Another study of nearly 8000 mothers in Massachusetts and Ohio found that although only 18% of mothers placed their babies on their stomachs to sleep when their babies were 1 month old, a number of the mothers changed to this position by the time the infants were 3 months old, increasing the rate to 29%. The authors say the increase results from influences on the mother from family friends, other children, and the infant’s own behaviors.
The studies’ research suggests that further educational programs to reduce prone sleeping be aimed at groups found to be at higher risk, including mothers who are African American or Hispanic, lower income, younger than 29, have a previous child, or have infants younger than 8 weeks. The researchers also encourage hospitals to reinforce the correct sleeping position by placing newborn infants to sleep on their backs while in the hospital.


Researchers do not know what causes SIDS. However, they have identified factors that increase the chances of SIDS:

  • Babies who sleep on their stomachs

  • Babies exposed to tobacco smoke

  • Mothers who smoke during pregnancy

  • Mothers who are less than 20 years old at time of first pregnancy

  • Babies born to mothers who had no or late prenatal care

  • Premature or low birth weight babies

  • Cold weather months

  • Baby boys


Although there is no sure way to prevent SIDS, possible ways to lower the risks include:

  • Placing babies to sleep on their backs

  • Good prenatal care

  • A smoke-free environment

  • Using a firm mattress

  • Not placing soft material like pillows or blankets under the baby

  • Not overheating babies (with clothing, heavy bedding, or very warm room temperature)

  • Breast feeding

  • Routine check-ups and immunizations

  • Closely observing babies for several days after a minor illness



  • National Institute of Child Health and Human Development
    "Back to Sleep" Campaign
    31 Center Drive, Room 2A32
    MSC 2425
    Bethesda, MD 20892-2425
    (800) 505-CRIB

  • Sudden Infant Death Syndrome Alliance
    (800) 221-SIDS

  • American Academy of Pediatrics
    SASE (business size) to:
    SIDS Fact Sheet
    AAP, PO Box 927
    Elk Grove Village, IL 60009


Adapted with Permission from JAMA Patient Page, July 1998 (not copyrighted).