What is SIDS?

SIDS is when a baby who seems healthy dies while sleeping. It's the number one cause of death in babies between one month and one year of age.

What causes it?

No one knows exactly. It might be caused by a problem in the part of the brain that controls breathing and waking up. Doctors think SIDS happens when a baby with this problem falls asleep in a dangerous position or place.

Is my baby at risk?

Most deaths from SIDS happen between two and four months of age. Native American and black babies are about twice as likely as white babies to die from SIDS. It happens more often in boys, and it's more common when the weather is cold.

What can I do to keep my baby safe?

There are some things you can do before your baby is born to lower the risk of SIDS. Get early and regular prenatal care. Don't smoke, drink, or use drugs while you're pregnant. After your baby is born, don't let anyone smoke near him or her. Babies who breathe secondhand smoke are at higher risk of SIDS.

The most important thing you can do is make sure your baby is safe while sleeping. Always put your baby on his or her back to go to sleep. Babies who sleep on their stomach or side are at higher risk of SIDS. Once your baby can roll over, it's okay to let him or her sleep in the position that's most comfortable.

Always put your baby to sleep in a crib or bassinet. It's dangerous to share a bed with your baby while you're sleeping. It's especially dangerous when your baby is younger than three months, or if either parent smokes or has been drinking. If you have twins or other young children who still sleep in a crib, use separate cribs instead of letting them sleep together. Don't use cosleepers or other things that make it easier to share a bed. It's okay to bring your baby into your bed if he or she is crying or hungry, but make sure you put your baby back in the crib before you go to sleep.

It's a good idea to keep your baby's crib next to your bed, or at least in your room. Use a firm mattress with a fitted sheet. Make sure there are no gaps between the mattress and sides of the crib. Don't use bumper pads or soft bedding. Don't put pillows, blankets, or stuffed animals in the crib. Don't use wedges, rolled blankets, or anything else to keep your baby in place while he or she is sleeping. Never let your baby sleep on a waterbed, sheepskin, couch, armchair, or other soft surface.

Make sure your baby doesn't get too warm while sleeping. Keep the room at a temperature that's comfortable for an adult in light clothing. Your baby should be warm but not overdressed. Don't use caps or anything else that covers your baby's head while he or she is sleeping.

Keep your baby's car seat in the car. Don't bring it into the house for your baby to sleep in.

Here are other things you can do to lower the risk of SIDS:

• Breastfeed, if possible. Breastfed babies are much less likely to die from SIDS.

• If your baby has reflux, be sure to follow your doctor's feeding instructions. Your baby should still sleep on his or her back.

• Make sure your baby has regular checkups and gets all recommended vaccinations. This makes SIDS much less likely.

• Don't rely on a baby monitor to make sure your child is safe while sleeping.

• Consider putting your baby to sleep with a pacifier for the first year. If he or she won't take the pacifier, don't force it. Pacifiers may lower the risk of SIDS. If you're breastfeeding, wait until after your baby is one month old so that the pacifier doesn't interfere with feeding.

Will putting my baby to sleep on his or her back cause flat spots on the back of the head?

Some babies do get flat spots on the back of the head from spending too much time on their backs. This is easily treated by turning your baby's head to a different side each time you put him or her in the crib, and by having plenty of “tummy time” while your baby is awake. Most babies' heads return to a normal shape by the time they're two years old.