Safe Sleep for Babies: A Complete Guide to Reducing SIDS Risk

Creating a safe sleep environment is one of the most important things you can do to protect your baby. Since the "Back to Sleep" campaign began in 1994, SIDS rates in the United States have dropped by more than 50%. Yet sleep-related deaths remain a leading cause of infant mortality, with approximately 3,500 babies dying each year from SIDS and other sleep-related causes. Understanding and implementing safe sleep guidelines can significantly reduce this risk. AAP

Understanding SIDS and Sleep-Related Deaths NIH

Sudden Infant Death Syndrome (SIDS) is the unexplained death of a baby younger than one year old, usually during sleep. It's sometimes called "crib death," though this is a misnomer—SIDS can happen anywhere a baby sleeps, and safe cribs themselves are not the cause. SIDS is part of a larger category called Sudden Unexpected Infant Deaths (SUID), which also includes accidental suffocation and strangulation in bed.

SIDS peaks between 1-4 months of age, with 90% of cases occurring before 6 months. The exact cause remains unknown, but researchers believe it involves a combination of factors: an underlying vulnerability in the infant (possibly related to brainstem development affecting arousal), a critical developmental period, and external stressors like unsafe sleep position or environment. NIH

While we can't change the underlying vulnerabilities, we can eliminate the external stressors. That's what safe sleep guidelines are designed to do.

The ABCs of Safe Sleep AAP

The American Academy of Pediatrics simplifies safe sleep into the ABCs:

A is for Alone. Your baby should sleep alone in their own sleep space. This means no bed-sharing with parents or siblings, no stuffed animals, no pillows, no blankets, no bumper pads, and no other items in the sleep space. The only things in the crib should be your baby and a fitted sheet.

B is for Back. Place your baby on their back for every sleep—naps and nighttime, every single time. This is the single most important thing you can do to reduce SIDS risk. Back sleeping reduces the risk of SIDS by approximately 50% compared to stomach sleeping. AAP

C is for Crib. Your baby should sleep on a firm, flat surface specifically designed for infant sleep—a safety-approved crib, bassinet, portable crib, or play yard. The mattress should be firm (press on it—if it holds an indentation, it's too soft), flat (no incline), and fit snugly in the frame with no gaps.

Sleep Position: Why Back Is Best AAP

The recommendation for back sleeping is based on decades of research and has been the single most effective intervention in reducing SIDS. Before the Back to Sleep campaign, many parents placed babies on their stomachs, believing this prevented choking. Research has definitively shown this is not the case—healthy babies placed on their backs are not more likely to choke. NIH

When babies are on their backs, their airway is clear and above the esophagus. Even if a baby spits up, gravity and natural reflexes help clear the milk or liquid. The same reflexes don't work as well when a baby is face-down.

Once your baby can roll both ways independently—typically around 4-6 months—you can stop worrying about repositioning them if they roll over during sleep. But always start every sleep on the back. The ability to roll indicates that your baby has developed enough strength and coordination to protect their airway. AAP

Side sleeping is also not recommended. Babies placed on their sides can easily roll to their stomachs, and the side position itself is less stable and carries similar risks to stomach sleeping.

Creating a Safe Sleep Environment AAP

The sleep surface matters enormously. Use only a firm, flat mattress that fits snugly in a safety-approved crib, bassinet, play yard, or portable crib. There should be no gap larger than two fingers between the mattress and the frame. Never use a mattress from another product, and never add padding to make a firm mattress softer.

A bare crib is a safe crib. The only thing that should be on the mattress is a tight-fitting sheet—nothing else. No blankets, quilts, comforters, pillows, bumper pads, sleep positioners, or stuffed animals. These items may look cozy, but they all increase the risk of suffocation or entrapment. AAP

Temperature regulation helps reduce risk. Overheating is associated with increased SIDS risk. Keep the room at a comfortable temperature (ideally 68-72°F) and dress your baby in light sleep clothing—generally one layer more than you would wear. Feel your baby's chest or back of neck to check if they're too hot; hands and feet may feel cool and that's normal. Never put a hat on your baby for indoor sleep. NIH

Wearable blankets or sleep sacks are the safe way to keep your baby warm without loose bedding. These zip or snap on and can't cover the face or bunch up around the baby.

Products That Are NOT Safe for Sleep AAP

Many products marketed for infant sleep are actually dangerous. The AAP recommends against:

Inclined sleepers like the Fisher-Price Rock 'n Play and similar products have been recalled and should never be used for sleep. The incline can cause a baby's head to fall forward, restricting breathing. Multiple infant deaths led to these recalls.

Sitting devices including car seats, swings, strollers, and bouncers are not safe for sleeping, even though babies often fall asleep in them. If your baby falls asleep in a car seat during travel, move them to a flat, firm surface as soon as you arrive at your destination.

Soft bedding of any kind—memory foam, pillow-top mattresses, waterbeds, or any surface that conforms to baby's shape—significantly increases suffocation risk.

Weighted blankets, weighted swaddles, and weighted sleepwear are not recommended. There is no evidence they help babies sleep better, and they may pose suffocation or overheating risks.

Crib bumper pads were banned for sale in the United States in 2022 due to suffocation, strangulation, and entrapment risks. This includes padded, mesh, and "breathable" bumpers.

Home monitors marketed to prevent SIDS have not been proven to reduce SIDS risk. The AAP does not recommend them as a strategy for reducing SIDS.

Room Sharing Without Bed Sharing AAP

The AAP recommends that babies sleep in the parents' room, close to the parents' bed, but on a separate surface designed for infants. This is called room sharing, and it's protective—studies show it reduces SIDS risk by up to 50% compared to babies sleeping in a separate room. Room sharing also makes nighttime feeding and monitoring easier.

Bed sharing—where the baby sleeps in the adult bed—is different and is not recommended. Bed sharing increases the risk of SIDS and other sleep-related deaths, particularly in the following circumstances: when a parent has consumed alcohol or sedating medications, when a parent smokes, when the baby was born preterm or with low birth weight, when the baby is younger than 4 months, and when the bed has soft bedding or pillows. AAP

If you're concerned about falling asleep with your baby, create the safest possible environment before you begin feeding: remove pillows and blankets, keep baby on a firm surface, and have your bed away from the wall to prevent entrapment. If you do fall asleep with your baby, move them to their own safe sleep space as soon as you wake.

Couches and armchairs are the most dangerous places for a baby to sleep. Never feed your baby in these locations if there's any chance you might fall asleep. The risk of sleep-related death is 50 times higher when a baby sleeps on a couch or armchair. AAP

Protective Factors: What Helps AAP

In addition to safe sleep environment, several factors have been shown to reduce SIDS risk:

Breastfeeding is protective against SIDS. Any amount of breastfeeding helps, and exclusive breastfeeding is even more protective. The protection continues even if you're combining breast and bottle.

Pacifier use at bedtime and naptime is associated with reduced SIDS risk. You don't need to replace the pacifier if it falls out during sleep. If you're breastfeeding, wait until breastfeeding is well established (usually around 3-4 weeks) before introducing a pacifier.

Prenatal care and avoiding substance use during pregnancy and after birth reduces risk. Smoking during pregnancy increases SIDS risk, as does exposure to secondhand smoke after birth.

Immunizations are protective. Babies who are up to date on their vaccines have a lower risk of SIDS.

Tummy Time: When Awake and Supervised AAP

While back sleeping is essential, tummy time while your baby is awake and supervised is important for development. Tummy time strengthens neck, shoulder, and arm muscles; prevents flat spots on the back of the head (positional plagiocephaly); and helps develop motor skills.

Start tummy time from the first days home from the hospital, beginning with just a few minutes several times a day. Place baby on your chest or across your lap if they protest being on the floor. Gradually increase the time as baby gets stronger.

The phrase to remember: "Back to sleep, tummy to play."

What About Swaddling? AAP

Swaddling can be calming for newborns and may help them sleep better. If you choose to swaddle, do it safely. Stop swaddling as soon as your baby shows signs of trying to roll over—typically around 2 months—because a swaddled baby who rolls to their stomach cannot use their arms to push up and protect their airway.

When swaddling, make sure the swaddle is snug around the arms but loose around the hips to allow healthy hip development. The baby should always be placed on their back, and the swaddle should not be so tight that it restricts breathing.

When to Transition Out of Your Room AAP

The AAP recommends room sharing for at least the first 6 months, and ideally for the first year. After that, you can move your baby to their own room when it feels right for your family. Continue to follow safe sleep practices in whatever room your baby sleeps.

The Bottom Line

Safe sleep practices save lives. The guidelines may seem restrictive, but each recommendation is based on research into what protects babies. Every sleep—naps and nighttime—matters. Consistency is key, and every caregiver (grandparents, babysitters, daycare providers) should follow the same guidelines.

Remember the ABCs: Alone on their Back in a Crib. A bare crib with just a fitted sheet. No soft objects, loose bedding, or bumpers. Room share but don't bed share. And always, always place baby on their back.

Clara is here to answer your questions about safe sleep and help you create the safest possible environment for your baby!