Science Says: Co-Sleeping Might Not Be As Dangerous As We All Thought

From the moment you enter the postpartum room with your newborn baby, you’re bombarded with messages about the dangers of co-sleeping. “Back to Sleep” posters adorn the walls, along with the “ABCs” of safe sleep: Alone, on their Back, in a Crib. If you doze off with your baby in your arms (because, y’know… giving birth is really tiring), you’re guaranteed an unwanted wake-up and a stern lecture from the nurse. 

Of course, everyone just wants your baby to be safe. But is co-sleeping really as dangerous as we’ve all been led to believe? Some experts are beginning to look more closely at the numbers and nuances, and say: maybe not.

RELATED: Science Says to Stop Feeling Guilty About How Your Family Sleeps

Why Co-Sleep with Your Baby?

If bed-sharing is so dangerous that hospitals warn against it, why do so many families do it? According to a recent report from NPR, the number of families who report co-sleeping with infants has risen from 6% in 1993 to 25% in 2015.

For sleep-deprived moms, the benefits can seem very clear. Babies’ immature stomachs need to eat frequently to stay nourished, and they don’t care if it’s 3 p.m. or 3 a.m. Getting out of bed for multiple middle-of-the-night feedings is exhausting. But when your baby’s right there, snuggled up against you, all you have to do is whip out a boob and you can both get back to sleep. It’s probably why over 40% of cultures worldwide, from Mexico to Japan, practice bed-sharing openly and regularly, and consider it part of their culture. 

James McKenna, an anthropologist at Notre Dame University, has been studying co-sleeping for nearly 40 years. He even developed the Mother-Baby Behavioral Sleep Laboratory to study exactly what happens when moms and babies share a bed.

What he found was astounding. When breastfeeding moms and babies sleep together, they instinctively turn to face each other. The baby positions his or her head to face the mother’s breast, and the mom curls around the baby to create a protective shell. Within this shell, the mother’s heartbeat and breathing mimic the comforting noises the baby remembers from the womb, while her breath against the baby’s face serves as a gentle reminder to breathe. Moreover, McKenna found that while sleeping next to each other, both mom and baby will wake more frequently but less thoroughly, which leads to more frequent breastfeeding and better nutrition, and can help new moms feel better rested. He also argues that this frequent waking may actually help prevent SIDS, since both parent and baby are more alert to risk factors such as dangerous positioning or the presence of a pet or pillow close to the baby’s head. 

A Look at the Numbers

According to NPR, a low-risk baby (one carried to term, with a healthy birth weight, whose parents do not drink excessively, use drugs, or smoke) has a 1 in 46,000 chance of dying in their sleep while following the American Association of Pediatricians’ (AAP) recommendation of sleeping alone in a crib in a parent’s room. This risk climbs to 1 in 16,400 when the same baby shares the parents’ bed—which may seem like a lot, but is actually only a .004% difference. By contrast, your baby has a 1 in 13,000 chance of being struck by lightning in his or her lifetime, and a 1 in 50 chance of developing a peanut allergy as a child. 

So why are doctors so afraid of bedsharing? In the early 2000s, a series of studies found a substantial correlation between co-sleeping and Sudden Infant Death Syndrome (SIDS). However, these studies failed to take risk factors such as pre-term birth, parental drinking, smoking, and drug use, and co-sleeping on a sofa instead of a bed into consideration. 

More recent studies found that a high-risk baby (defined as one with a low birth weight, parents who smoke, and a mother who regularly has two or more drinks) has a 1 in 150 chance of dying of SIDS while co-sleeping. However, it’s really important to note that this baby had a 1 in 1500 chance of dying of SIDS while following the AAP’s recommendation of sleeping alone in a crib in the parents’ bedroom. That’s a ten-fold increase—compared to only .004% for a low-risk baby. 

In a nutshell, what this tells us is that co-sleeping can be really dangerous for babies who already have other risk factors present. For low-risk babies, it carries less risk than riding in a car

Making Bed-Sharing Safe

So let’s assume that you don’t drink, smoke, or use drugs, and your baby was carried to term with a healthy birth weight. If you want to co-sleep, you can do so pretty safely by following a few simple precautions. La Leche League, the international breastfeeding safety and support organization, suggests these 7 Safe Sleep Guidelines

  1. No Smoking. This includes the mom (obvs) but also any other partners sharing the bed, and means no smoking ever—even outside. Smoke can linger on clothes and skin and affect babies’ respiratory health
  2. Sober Parents. This means no alcohol (again, duh) but also no medications that cause drowsiness. 
  3. Nursing Mother. Research indicates that breastfeeding moms sleep more lightly and are more in tune with their babies’ night wakings. 
  4. Healthy Baby. Carried to term, and with a healthy birth weight. 
  5. Baby on Back. Just like those ABC’s they drill into you in the hospital, co-sleeping babies should be placed to sleep flat on their back. 
  6. No Swaddling. Instead, dress baby in a onesie or close-fitting footie pajamas. 
  7. Safe Surface. The sleeping surface should be firm (no beanbags, waterbeds, super fluffy mattress toppers, etc), and clear of toys, extra pillows, and plush comforters. Many co-sleeping parents choose to only pull the blanket up to their waist and sleep in a cardigan or sleep shirt to keep covers away from babies’ faces. Keep strings and cords (window shade pull-cords, phone charging cables, etc) far away, and reduce the risk of falling by either placing the mattress on the floor or pushing the bed up against the wall and stuffing any cracks with rolled up receiving blankets or towels so Baby won’t suffocate. Most co-sleeping families feel safest with the baby sleeping between Mom and the wall. Never let older children or pets share a bed with a newborn baby sleeping in it. 

You can learn more about safe co-sleeping, and access handy charts and even a little safe co-sleeping song, at La Leche League’s website

Do you co-sleep with your baby? Or are you considering it? Sound off in the comments!

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