
Sudden infant death syndrome (SIDS) is the unexplained death, usually during sleep, of a seemingly healthy baby. Although the exact cause is still unknown, it appears that sudden infant death syndrome may be associated with problems in the portion of an infant’s brain that controls breathing and arousal from sleep. Other risk factors of SIDS include sleeping on the stomach or side, on a soft surface, or with parents in the same sleep space.
SIDS is a scary thing to think about, but there are multiple ways to help reduce your baby’s risk of SIDS and put your baby safely to sleep.
‘Back’ to sleep
Always place your baby on his or her back to sleep, even for naps. This is the safest sleep position for reducing the risk of SIDS. Research shows that babies who are put to sleep on their stomachs are much more likely to die of SIDS than are babies placed on their backs. Infants who sleep on their sides also are at increased risk, probably because babies in this position can roll onto their stomachs.
Since 1992, when the American Academy of Pediatrics (AAP) began recommending the back-sleeping position for infants, the incidence of SIDS in the United States has declined significantly.
The only exceptions to the back sleeping rule are babies who have health problems that require them to sleep on their stomachs because the risk of death is greater if they sleep on their backs. If your baby was born with a birth defect, spits up often after eating, or has a breathing, lung or heart problem, talk to your baby’s medical provider about the best sleeping position for your child.
Make sure that everyone who takes care of your baby knows to place your baby on his or her back for sleeping. That may include grandparents, child care providers, baby sitters, friends and others. Be firm in your instructions. Placing babies on their backs to sleep is based on evidence that doing so saves infant lives.
Some babies don’t like sleeping on their backs at first, but they get used to it quickly. Many parents worry that their baby will choke if he or she spits up or vomits while sleeping on his or her back, but researchers have found no increase in choking or similar problems.
A baby who sleeps on his or her back may develop a flat spot on the back of the head. For the most part, this will go away after the baby learns to sit up. You can help keep your baby’s head a normal shape by alternating the direction your baby lies in the crib — head toward one end of the crib for a few nights and then toward the other. This way, the baby won’t always sleep on the same side of his or her head.
Once your baby can successfully roll over from back to stomach and then back again — typically around age 6 months — you can let him or her sleep in the position he or she chooses. But until your baby becomes adept at moving around on his or her own, keep your baby’s bassinet or crib free of loose bedding or stuffed animals. This is to prevent your baby from rolling into them and being unable to roll out.
Share the room, not the bed
Many new parents are tempted to take their baby into bed with them. This is often because they’re tired — understandably so! — and because having baby in bed seems more convenient. And for some parents, this is what their parents and grandparents did before them.
But the truth is that bed sharing can increase the risk of harm to your baby. Adult beds generally have softer mattresses than cribs and have lots of blankets and pillows. Though comfortable for adults, these factors can interfere with baby’s breathing or make a baby overly warm. In addition, there’s a risk of the adult inadvertently rolling over onto the baby during sleep or pushing the baby into bedding and causing suffocation.
Falling asleep with your baby on a couch or chair can be even more dangerous because of the cramped quarters. In addition, if your child learns to sleep well in your bed, it can make transitioning to his or her own bed later more difficult and traumatic. As your child gets older, it can be harder to break a bedsharing habit.
Instead of bed sharing, the AAP recommends room sharing during your baby’s first year, or at least for the first six months. The rates of SIDS and other sleep-related deaths are highest during this time.
Room sharing means your baby sleeps in your room with you but in a separate bassinet, crib or other structure designed for infants. Having your baby nearby can put your mind at rest and make it easier to monitor your baby. Evidence suggests that sharing a room with your baby, but not the bed, can decrease your baby’s risk of SIDS by as much as half.
A safe sleep space
Make sure your baby is comfortable and safe. If you’ve made sure the crib and area around it are safe, you won’t immediately become concerned about your baby’s safety if you hear cries. Follow these safety guidelines.
- Avoid old cribs or bassinets. Even if an old crib is in good shape, safety standards have improved over the years, so it’s generally a good idea to buy a new crib if you can. If you do use a hand-me-down crib, make sure that it meets current safety standards. Older cribs with drop sides — the kind that have a side rail that moves up and down — are not considered safe. In addition, some older cribs may have been coated with lead paint, which is a health hazard. A crib should be the one place you feel comfortable leaving your child alone.
- Check the slat spacing. The crib’s slats should be no farther apart than 2 3/8 inches. This applies to bassinets, too. If you can fit a can of soda through the slats, the openings are too large. You’re more likely to find this problem in older cribs, but you can’t be too safe when it comes to your baby, so check any crib you put him or her in.
- Get the right mattress. The surface of your baby’s mattress should be firm, flat and smooth. Make sure the mattress fits snugly within the frame of the product it’s made for, so there’s no space for your baby to get trapped.
- Remove extraneous items. During the first year — or at least until your baby can easily move around the crib on his or her own — remove any extra bedding from the sleep space, such as bumper pads, pillows, cushions and comforters. This prevents your baby from rolling into a potentially suffocating situation. To keep your baby warm, try a sleep sack or other sleep clothing that doesn’t require additional covers. Save toys and stuffed animals for when your baby is awake and supervised.
- Remove crib mobiles early. Crib mobiles typically include string and small attached pieces. Make sure your little one can’t reach the mobile so that he or she can’t become entangled or pull anything off. When your baby is able to push up onto his or her hands and knees, the mobile should be removed from the crib.
- Safe swaddling. Many young babies fall asleep and sleep better when swaddled. If you swaddle your baby, use a breathable 100% cotton blanket or a swaddling sleep sack. A blanket is breathable when you can hold one layer of the blanket up to your mouth and your breath can pass through the fabric. This is the best option for a baby because the baby can still breathe if the fabric slips and covers his or her face. Cotton also allows body heat to escape, which prevents overheating. When swaddling your baby, make sure to allow room for the hips and legs to move freely. If you wrap your baby too tightly around the hips and legs, it can interfere with proper growth and joint development. Your baby’s legs should be able to bend up and out. It’s time to stop swaddling when your baby first shows signs of rolling over, generally around 4 months. Ideally, a baby needs to be able to control his or her arms when rolling. But the baby can’t do that when he or she is swaddled.
- Try a pacifier. Sucking on a pacifier at nap time and bedtime may reduce the risk of SIDS. One caveat — if you’re breast-feeding, you may want to wait to offer a pacifier until breast-feeding is well established. For some babies, this can be 3 to 4 weeks of age. If your baby’s not interested in the pacifier, try again If the pacifier falls out of your baby’s mouth while he or she is sleeping, there’s no need to pop it back in.

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