What is sudden infant death syndrome (SIDS)?

SIDS stands for Sudden Infant Death Syndrome. It is when a baby dies and they are less than one year old and the cause is not known. SIDS affects families of all races, religions, and income. The babies seem healthy before SIDS happens.
SIDS stands for ʺSudden Infant Death Syndromeʺ. It is the unexplained death of a child younger than 1 year old.
Sudden Infant Death Syndrome (SIDS) is the diagnosis given for the sudden death of a baby under one year of age that remains unexplained after a complete investigation, including an autopsy, examination of the death scene and review of the symptoms or illnesses the baby had prior to dying and any other pertinent medical and family history.

Because most babies sleep in cribs, and therefore, most cases of SIDS occur when a baby is in a crib sleeping, SIDS is sometimes called "crib death." Cribs do not cause SIDS. However, other aspects of an infant’s sleep environment have been associated with increasing the risks for SIDS.

A SIDS diagnosis falls under a broader classification of infant deaths called Sudden Unexpected Infant Death (SUID). There are 4,500 SUIDs in the United States each year, including more than 2,200 SIDS deaths. Of these SIDS/SUID deaths, statistics indicate that as many as 80-90% may be the result of unsafe sleep practices.
Charles J. Sophy, MD
Adolescent Medicine

Sudden infant death syndrome (SIDS) is the unexplained death, usually during sleep, of a seemingly healthy baby. Sudden infant death syndrome is sometimes known as crib death because the infants often are found dead in their cribs.

Although the exact cause is still unknown, it appears that sudden infant death syndrome may be associated with abnormalities in the portion of an infant's brain that controls breathing and arousal from sleep.

Deborah Mulligan
Deborah Mulligan on behalf of MDLIVE
A lack of answers is part of what makes sudden infant death syndrome (SIDS) so frightening. SIDS is the leading cause of death among infants 1 month to 1 year old, and claims the lives of about 2,500 babies each year in the United States. Some people call SIDS "crib death" because many babies who die of SIDS are found in their cribs.

Research has proven that parents can take certain measures to minimize the risk of SIDS ever happening. The “Back to Sleep” Campaign is promoted by the American Academy of Pediatrics and various other health organizations. First and foremost, infants younger than 1 year old should always be placed on their backs to sleep — never face-down on their stomachs. Grandparents will tell you that babies sleep better on their tummies.  They might be right; however numerous studies have proven that this sleep position significantly increases the risk of sudden death.  A common fear is that by putting babies on their back to sleep may cause them to throw up and choke.  Actually a recent study came to the opposite conclusion.  A study of several thousand infants found that babies who slept on their backs had less congestion and choking.

Since 1992, the American Academy of Pediatrics has recommended that infants be placed to sleep on their backs to reduce the risk of sudden infant death syndrome (SIDS), also called crib death. SIDS is the sudden and unexplained death of a baby under 1 year of age. Even though there is no way to know which babies might die of SIDS, there are some things that you can do to make your baby safer:

Always place your baby on his or her back to sleep, even for naps. This is the safest sleep position for a healthy baby to reduce the risk of SIDS. Place your baby on a firm mattress, such as in a safety-approved crib. Research has shown that placing a baby to sleep on soft mattresses, sofas, sofa cushions, waterbeds, sheepskins, or other soft surfaces raises the risk of SIDS. Remove soft, fluffy, and loose bedding and stuffed toys from your baby's sleep area. Make sure everyone who cares for your baby knows to place your baby on his or her back to sleep and about the dangers of soft bedding. Talk to child care providers, grandparents, babysitters, and all caregivers about SIDS risk. Remember, every sleep time counts. Make sure your baby's face and head stay uncovered during sleep. Keep blankets and other coverings away from your baby's mouth and nose. The best way to do this is to dress the baby in sleep clothing so you will not have to use any other covering over the baby. If you do use a blanket or another covering, make sure that the baby's feet are at the bottom of the crib, the blanket is no higher than the baby's chest, and the blanket is tucked in around the bottom of the crib mattress. Do not allow smoking around your baby. Don't smoke before or after the birth of your baby and make sure no one smokes around your baby. Don't let your baby get too warm during sleep. Keep your baby warm during sleep, but not too warm. Your baby's room should be at a temperature that is comfortable for an adult. Some mothers worry if the baby rolls over during the night. However, by the time your baby is able to roll over by herself, the risk for SIDS is much lower. During the time of greatest risk, 2 to 4 months of age, most babies are not able to turn over from their backs to their stomachs.

This answer is based on source information from the National Women's Health Information Center.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.