Sudden Infant Death Syndrome (SIDS) Facts

by National Institute of Health

What is SIDS?

Sudden Infant Death Syndrome (SIDS) is the term for the sudden death of an infant under 1 year of age that remains unexplained after a complete investigation, including:

• An autopsy.
• Examination of the death scene.
• Review of any symptoms or illnesses the infant experienced before dying.
• Any other important medical history.

Because most SIDS deaths occur while infants are sleeping in a crib, SIDS is commonly referred to as "crib death." However, cribs do not cause SIDS.

What is the Impact of SIDS in the U.S.?

Approximately 3,000 babies die of SIDS each year. Even though doctors and nurses still don't know what causes SIDS, they do know:

• Most SIDS deaths occur when a baby is between 2 and 4 months of age.
• African American babies are twice as likely to die of SIDS as white babies.
• More boys die of SIDS than girls.
• A SIDS death happens quickly, with no signs of suffering.
• More SIDS deaths occur in the colder months.

How Can I Reduce the Risk of SIDS?

Before the 1992 recommendation by the American Academy of Pediatrics to place infants on their sides or backs to sleep to reduce SIDS, more than 5,000 babies in the U.S. died from SIDS every year. Since then, as tummy sleeping has declined, that number has been reduced to less than 3,000 each year. Below is a list of recommendations to reduce the risk of SIDS.

• Place your baby on his or her back to sleep, at nighttime and naptime. This is the best way to reduce the risk of SIDS.
• Place your baby on a firm mattress, such as in a safetyapproved crib.
• Remove all fluffy and loose bedding and other soft items from the sleep area.
• Make sure your baby's head and face stay uncovered during sleep.
• Don't smoke before or after the birth of your baby.
• Don't let your baby get too warm during sleep.

Actions to Reduce the Risk of SIDS

Always place your baby on his or her back to sleep. Make sure that all caregivers place your baby to sleep on his or her back. This is the single most important thing you can do to reduce the risk of SIDS.

Place your baby on a firm mattress, such as in a safety-approved crib. Don't put your baby to sleep on a soft mattress, sofa, sofa cushion, waterbed, sheepskin, or other soft surface.

Remove all fluffy and loose bedding from the sleep area. Make sure all pillows, quilts, stuffed toys, and other soft items are out of the sleeping area.

Make sure your baby's head and face stay uncovered during sleep. Keep your baby's mouth and nose clear of blankets and other coverings during sleep. Use sleep clothing with no other covering over the baby. If you use a blanket or another covering, make sure your baby is "feet to foot" in the crib. Feet to foot means 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 crib mattress, making it unlikely the baby can slip under the blanket.

Don't let your baby become too warm while sleeping. Your baby should be kept warm, but not too warm. Too many layers of clothing or blankets can overheat your baby. Also, keep the temperature in the baby's sleep area at a level that is comfortable for you.

Don't smoke before or after the birth of your baby. Make sure no one smokes around your baby. SIDS is more common among babies who are exposed to smoke from tobacco during or after pregnancy.

Take your baby for well-baby check-ups. Make sure your baby doesn't miss any well-baby check-ups and receives his or her shots on time.

Get good health care. Good care starts early in pregnancy and includes eating the right foods. Don't smoke, use drugs, or drink alcohol while you are pregnant. You should also have frequent check-ups with your doctor or nurse.

Responses to Questions About SIDS

Can my baby choke while sleeping on his or her back?

Some mothers worry that babies who sleep on their backs will choke if they spit up or vomit while sleeping, but babies automatically swallow or cough up such fluid. In fact, doctors have found no increase in choking or other problems in babies who sleep on their backs.

What's wrong with my baby sleeping on his or her stomach? I was placed to sleep on my stomach.

Doctors have no way of knowing which babies will die of SIDS, but they do know some actions to reduce the risk. In 1992, when the American Academy of Pediatrics first recommended back or side sleeping to reduce the likelihood of SIDS, more than 5,000 babies in the U.S. died from SIDS every year. Since then, as tummy sleeping has decreased, that number has been reduced to less than 3,000 each year.

What if my baby can't adjust to sleeping on his or her back?

Some babies don't like sleeping on their backs at first, but most get used to it quickly. The earlier you start placing your baby on his or her back to sleep, the more quickly he or she will become used to the position. Also, babies can benefit from sleeping on their backs. Babies who are on their backs can move their arms and legs and look around more easily.

Is it okay if my baby sleeps on his or her side?

Although the side position is safer than the stomach position, babies who sleep on their sides are in danger of rolling onto their stomachs. If you choose to place your baby on his or her side to sleep, make sure the baby's lower arm is in front of the baby to help stop him or her from rolling onto the stomach.

What about new products designed to keep my baby in a certain position during sleep?

There is no proof that any such products will help lower the risk of SIDS. Back sleeping is the best position to reduce SIDS risk. 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.

What if my baby's grandparents or caregivers want to place my baby to sleep on his or her stomach at naptime?

Make sure everyone knows to place your baby on his or her back to sleep at naptime and nighttime. Explain to everyone why back sleeping is the best.

Are there times when my baby should be on his or her stomach?

Yes, your baby should have plenty of "tummy time" when he or she is awake and being watched. This also helps make your baby's neck and shoulder muscles stronger.

Will my baby get "flat spots" on the back of his or her head from back sleeping?

Flat spots on the back of a baby's head are usually a temporary condition that goes away a few months after the baby begins to sit up. Tummy time, when your baby is awake, is a good way to reduce flat spots.

At what age is a SIDS death likely to happen?

SIDS is the sudden death of a child under 1 year of age. It is the leading cause of death for infants after 1 month of age and occurs most frequently between the second and fourth month. The incidence of SIDS drops dramatically after 6 months of age.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.