Frequently Asked Questions (FAQs) About SIDS and Safe Infant Sleep

SIDS stands for "Sudden Infant Death Syndrome," and is the sudden, unexplained death of a baby younger than 1 year of age that doesn't have a known cause even after a complete investigation. This investigation includes performing a complete autopsy, examining the death scene, and reviewing the clinical history.

When a baby dies, healthcare providers, law enforcement personnel, and communities try to find out why. They ask questions, examine the baby, gather information, and run tests. If they can't find a cause for the death, and if the baby was younger than 1 year old, the medical examiner or coroner may call the death SIDS.

SUID stands for "Sudden Unexpected Infant Death." SUID is defined as deaths in infants younger than 1 year of age that occur suddenly and unexpectedly, and whose cause of death is not immediately obvious prior to investigation.

SUID includes all unexpected deaths: those from a known cause, and those from unknown causes. SIDS and suffocation are both types of SUID. About one-half of all SUID cases are SIDS. Many unexpected infant deaths are accidents, but a disease or something done on purpose can also cause a baby to die suddenly or unexpectedly. For some SUID, a cause is never found.

Other sleep-related infant deaths are those that occur in the sleep environment or during sleep time. They include accidental suffocation by bedding, entrapment (when a baby gets trapped between two objects, such as a mattress and wall, and can't breathe), or strangulation (when something presses on or wraps around a baby's neck, blocking the baby's airway). These deaths are not SIDS, but they are SUID.

The best way to protect baby during sleep is to always place them on their backs to sleep, in their own sleep space designed for babies and in the parents’ room, on a surface that is firm, flat, and level (not inclined) covered only by a fitted sheet, and with no objects, toys, or other items in the sleep area.

The majority (90%) of SIDS deaths occur before a baby reaches 6 months of age, and the number of SIDS deaths peaks between 1 month and 4 months of age.

However, SIDS deaths can occur anytime during a baby's first year, so parents should still follow safe sleep recommendations to reduce the risk of SIDS until their baby's first birthday.

The term “SIDS” applies to only infants younger than 1 year of age.

Research shows that swaddling does not decrease baby’s risk of SIDS. However, some babies are calmer and sleep better when they are swaddled. But, once baby starts to roll over on their own, swaddling increases risk of other sleep-related death by suffocation and strangulation.

Using the back sleep position for swaddled babies is especially important because sleeping on the stomach or side when swaddled increases the risk for SIDS and other sleep-related deaths.

The swaddle should not be too tight or make it hard for baby to breathe or move their hips. And caregivers should watch for signs of overheating, such as sweating or feeling hot to the touch, in a swaddled baby. 

If you choose to swaddle your baby, make sure you follow other safe sleep recommendations to reduce baby’s risk of sleep-related deaths. And stop swaddling baby when they start rolling over, usually around 3 months of age.

Research shows that the back sleep position carries the lowest risk of SIDS.

Research also shows that babies who sleep on their backs are less likely to get fevers, stuffy noses, and ear infections. The back sleep position makes it easier for babies to look around the room and to move their arms and legs.

Remember: Babies sleep safest on their backs, and every sleep time counts!

No. Healthy babies naturally swallow or cough up fluids—it’s a reflex all people have. Babies may actually clear such fluids better when sleeping on their backs because of the location of the opening to the lungs in relation to the opening to the stomach.

When on their back, baby’s trachea or windpipe (tube to the lungs) lies on top of the esophagus (tube to the stomach). Anything regurgitated,refluxed, or spit up from the stomach through the esophagus has to go against gravity to get to the windpipe and cause choking. When on the stomach, such fluids leave baby’s esophagus and pool at the opening for the windpipe, making choking more likely.

No. Your caregiver followed advice based on the evidence available at that time. Since then, research has shown that sleeping on the stomach increases the risk for SIDS, and that sleeping on the back carries the lowest risk of SIDS. That’s why the latest recommendation is: “back is best.”

The baby's comfort is important, but safety is more important. Parents and caregivers should place babies on their backs to sleep even if they seem less comfortable or sleep more lightly than when on their stomachs.

A baby who wakes frequently during the night is actually normal and should not be viewed as a "poor sleeper."

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 your baby will adjust to the position.

No. Babies placed to sleep on their sides are at increased risk for SIDS. For this reason, babies should sleep fully on their backs for naps and at night to reduce the risk of SIDS.

Once baby can roll from back to stomach and from stomach to back on their own, you can leave them in the position they choose after starting sleep on their back.

But, if they can only roll one way on their own, you should reposition them to their back if they roll onto their stomach during sleep.

If baby usually sleeps on their back, putting them on the stomach or side to sleep, for a nap or at night, increases the risk for SIDS by up to 45 times.

So it is important for everyone who cares for babies to always place them on their backs to sleep, for naps and at night, to reduce the risk of SIDS.

Pressure on the same part of the baby's head can cause flat spots if babies are laid down in the same position too often or for too long a time. Such flat spots are usually not dangerous and typically go away on their own once the baby starts sitting up. The flat spots also are not linked to long-term problems with head shape. Making sure your baby gets enough tummy time is one way to help prevent these flat spots. Limiting the time spent in car seats, once the baby is out of the car, and changing the direction the infant lays in the sleep area from week to week also can help to prevent these flat spots. Check out the other things parents and caregivers can do to prevent flat spots on the back of the head. Visit the Other Ways To Help Prevent Flat Spots on Baby's Head section of the website for more information.

Yes. Your baby should have “tummy time” when they are awake, and when someone is watching them. Supervised tummy time helps strengthen your baby’s neck and shoulder muscles, build motor skills, and prevent flat spots on the back of the head.

Learn more about the benefits of tummy time.

No. Research suggests that following safe sleep recommendations may be even more important when baby has a URI or other illness.¹ Having a recent illness with a high fever, called a febrile illness, is a risk factor for SIDS. Ill babies also overheat more easily because they may already have a fever or a higher-than-normal body temperature. Because infants sleeping on their stomachs are at higher risk for overheating than infant sleeping on their backs² parents and caregivers should continue to use the back sleep position when baby is sick. In addition, baby’s risk for injury or death in an adult bed is higher when the infant is sick, such as with a URI or the flu, so parents and caregivers should resist the urge to bring baby into bed for care and comfort. 

Ill infants are not as reactive and may be more lethargic or sluggish than infants who are well³ so they may not be able to adjust their mouth, nose, or head position to breathe better if their face gets covered. Parents and caregivers can help reduce risks for sleep-related death in babies who are ill by following safe sleep recommendations. That is: placing babies on their backs to sleep for naps and at night; using a firm, flat, and level sleep surface covered only by a fitted sheet; keeping babies’ sleep area in the parents’ room, close to their bed; and making sure baby does not overheat and keeping baby’s face and head uncovered during sleep. If a parent or caregiver is concerned about baby’s illness, they should contact a healthcare provider immediately.

Sharing an adult bed with baby, a practice known as bed sharing, increases the risk of SIDS, suffocation, and other sleep-related infant deaths.   

Sharing an adult bed, couch or armchair with baby can be risky, especially in some situations.

• Very high risk:
  • Sleep surface is soft, such as a waterbed, old adult mattress, couch, or armchair.
  • Adult is very tired, taking medication that makes them drowsy, using substances like alcohol, or whose ability to respond is affected in some way
  • Adult smokes cigarettes or uses tobacco products (even if they do not smoke in the bed)
• High risk:
  • Baby is younger than 4 months old (regardless of adult smoking or sleep surface)
  • Adult is not the baby’s parent, but is another caregiver, such as a grandparent or sibling
• Higher-than-normal risk:
  • Baby was born preterm (before 37 weeks) or born at a low birth weight
  • Sleep area includes unsafe items, such as pillows or blankets

Instead, healthcare providers recommend sharing your room with baby for at least the first 6 months. Room sharing means baby has their own sleep space (crib, bassinet, or portable play yard) in your room, separate from your bed. Room sharing is safer than sharing your bed with baby. It is also safer than putting baby in their own room. Room sharing also lowers baby’s risk for injury and death from situations like an adult or sibling accidentally rolling over them. Keeping baby’s sleep space close to your bed makes it easy to check on, feed, and comfort baby without having to get all the way out of bed.

Learn about room sharing as part of a safe sleep environment for your baby.

If you fall asleep while feeding or comforting baby in your bed, put them back in a separate sleep area as soon as you wake up. Research shows that the longer an adult shares a bed with baby, the higher baby’s risk for suffocation and other sleep-related death.

Before you bring baby into your bed for feeding or comforting, remove or clear away all soft items and bedding from your side of the bed. When finished, put baby back in a sleep area made just for babies, like a portable crib, close to your bed.¹ The Consumer Product Safety Commission has more information on crib safety at https://www.cpsc.gov/SafeSleep.

Currently, the American Academy of Pediatrics (AAP) Task Force on SIDS does not have enough evidence to recommend for or against using a cardboard box, a wahakura (a woven bassinet-like structure intended as a safe sleeping space for an infant), or a Pepi-Pod^® (a plastic version of a wahakura).

The use of any sleep area that is not safety-approved for infant sleep or that does not adhere to Consumer Product Safety Commission (CPSC) mandatory safety standards for infant sleep products is not recommended.

The AAP Task force recommends that parents and caregivers use a sleep surface for baby that is firm (returns to original shape quickly if pressed on), flat (like a table not a hammock in a safety-approved* crib), level (not at an angle or incline), and covered only with a fitted sheet.. 

Crib bumpers, bumper pads, and similar products that attach to crib sides, railings, or slats are often used with the intent of protecting babies from injury. However, evidence does not support using crib bumpers to prevent injury. In fact, crib bumpers can increase your baby’s risk of suffocation and wedging and can cause serious injuries or death. Keeping bumpers out of your baby’s sleep area is the best way to avoid these dangers.

Before crib safety was regulated, the spacing between the slats of the crib sides could be any width, which posed a danger to infants if the spaces were too wide. Parents and caregivers used padded crib bumpers to protect infants. Now that cribs must meet safety standards, the spaces between slats don’t pose the same dangers. As a result, bumpers are no longer needed.

In 2021, the President signed the Safe Sleep for Babies Act (PDF 185 KB), which prohibits the manufacture and sale of crib bumpers and certain inclined sleepers. 

Contact your state health department if you need help finding a safe sleep environment for your baby. Your state health department has resources and can connect you with local initiatives and groups that may be able to help you and your baby.

There is currently no product that can prevent SIDS because there is no known way to prevent SIDS.

Many wedges, positioners, or other products that claim to keep babies in one position or to reduce the risk of SIDS, suffocation, or reflux do not meet federal guidelines for sleep safety. These products, such as inclined sleepers, are linked to injury and death, especially when used in baby's sleep area. You can help prevent injuries and deaths by not using these products and devices.

The U.S. Food and Drug Administration, CPSC, AAP, and other organizations warn against using these products, because they are dangerous for babies.

Home heart and breathing monitors are not recommended as a primary way to detect SIDS.

If you choose to use devices that measure baby’s heart rate and breathing for reasons other than detecting SIDS, make sure to follow safe sleep recommendations to reduce baby’s risk of sleep-related deaths.

The NICHD-led Collaborative Home Infant Monitoring Evaluation study looked at babies who were at high risk for SIDS. The monitors were not effective at identifying situations that might lead up to SIDS. Based on this and other research findings, AAP recommends that caregivers not use these monitors to prevent SIDS or identify babies at risk for SIDS.

Healthcare providers might prescribe these products to manage certain medical conditions. If you have questions about using these devices for health problems or concerns other than SIDS, talk with your baby’s healthcare provider.

Keep in mind that breathing, heart, and other home monitors are different from baby monitors that allow caregivers to hear and/or see the infant from another room.

CPSC and the Juvenile Products Manufacturers Association advises parents and caregivers to check all baby monitors and other products with electrical cords to make sure they are out of baby’s reach. Monitors should be placed at least 3 feet away from any crib, bassinet, play yard, or other safe sleep environment.

Yes! Experts recommend skin-to-skin contact for all parents and newborns for at least 1 hour after birth, once a healthcare provider says the parent is stable and can respond to their baby. When the parent needs to sleep or handle other activities, baby should be placed on their back in their own sleep space, such as a safety-approved crib⁴ or bassinet.

Weighted blankets and swaddles are not recommended because there is not enough evidence of their safety for use with infants, and because—based on what we know about infant health, SIDS, and sleep-related infant deaths--they could actually cause harm.

All parents and caregivers should consider the following:

• An infant’s ribcage is still developing and adding weight could make it difficult for baby to expand their chest to take in air, reducing their ability to breathe properly. There are no studies of what amount of weight, if any, is safe to place on baby’s chest.
• Weighted swaddles and blankets are a new product category, meaning there are currently no safety standards for them beyond the general rules for children’s products (for example, lead content, likelihood to catch on fire, etc.). There are also no studies regarding the use of these products and the risk of sleep-related death. 
• If the infant rolls over during sleep, the additional weight could make it more difficult for them to roll onto their back again. Sleeping on the stomach carries the highest risk of SIDS. That risk is very high among infants who are used to sleeping on their back, but who are placed onto their stomachs for sleep, and among infants who are swaddled and who are placed or roll onto their stomachs.
• Because there are no safety regulations for these products, they could be made with heavy/thick materials that increase overheating risk. Overheating from excessive clothing or blankets and high room temperature are associated with an increased SIDS risk.
• Claims that these products are safe for infants during sleep are based on a single study of 16 infants in an intensive care unit with neonatal opioid withdrawal syndrome, in which the infants were constantly monitored and covered with a weighted blanket for only 30 minutes at a time. Because this tightly controlled situation is very different from using a weighted product on an infant for an hour or more at a time, without constant monitoring, the safety of product use in the home cannot be assumed.
• Suggested benefits of weighted blankets and swaddles for infants are unproven. Although there is some evidence suggesting that the products may be beneficial in certain groups of older children or adults, there are no studies that show any benefits specifically in infant groups.

One of the most important things to remember when a baby dies from SIDS is that the family are not to blame. The causes of SIDS remain unknown. Even though there are ways to help reduce the risk, there is no definitive way to keep SIDS from occurring.

A variety of resources are available to help families who have lost an infant to SIDS. Talking to other parents or caregivers who have lost an infant to SIDS may be helpful. A healthcare provider also may be able to recommend local resources and groups.

Parents can also find support at the community and state level through the National SUID/SIDS Resource Center and other organizations such as First Candle and Cribs for Kids^® .