Why is bed sharing among parents and infants — more commonly known as co-sleeping — so controversial?

Parents Sleeping In Bed With Newborn Baby
While bed sharing is common for families in many parts of the world, the practice is considered controversial in the U.S. (Photo: Getty Images)

Despite the fact that co-sleeping — or, more accurately, bed sharing — is common for families in many parts of the world, the practice is considered controversial in the U.S. But some experts say that's for a good reason.

"Sharing a bed with a parent occurs in many countries," Dr. Rafael Pelayo, a sleep specialist at Stanford Health Care, tells Yahoo Life. "It's a question of what's safe and convenient for the family." But when it comes to bed sharing with infants under 1 year of age, Pelayo explains that the practice is "not a question of culture — it's a public health issue. Sleeping in the same bed with an infant increases the risk of death."

Some experts point out, though, that American parents "seem to receive more strict guidance, especially from pediatricians, about avoiding co-sleeping," Sara Harkness, a professor and director of the Center for the Study of Culture, Health and Human Development at the University of Connecticut, told CNN. "This is part of a larger set of advice about sleeping arrangements, including not using padded 'bumpers' around cribs, having the baby sleep on its back and not using covers such as quilts or blankets for babies — all for the same purpose of avoiding the danger of suffocation."

The American Academy of Pediatrics guidance on safe sleeping to help prevent SIDS (sudden infant death syndrome) and other sleep-related infant deaths "discourages sharing a bed with a child under 1 year of age," explains Pelayo. According to the AAP, about 3,500 infants die each year in the U.S. from sleep-related causes, which include SIDS and accidental suffocation. The majority (90 percent) of SIDS deaths happen before a baby is 6 months old, according to the National Institutes of Health, but the agency notes that SIDS deaths can occur at any point during a baby's first year.

But James McKenna, director of the University of Notre Dame's Mother-Baby Behavioral Sleep Laboratory and author of Safe Infant Sleep, tells Yahoo Life that there's "negative rhetoric" around bed sharing and argues that the practice can be "modified and made safe — even protective — after specific risk factors are removed." Those risk factors include smoking or exposing infants to secondhand smoke, as well as drinking before bed to the point of intoxication or taking medications that have a sedative effect, both of which make parents significantly less alert to a baby in their bed.

McKenna adds that it's important to have a firm mattress and minimal bedding, and no soft objects or other children in the bed, while keeping the baby at chest level and on its back. Sleeping with a baby on a couch, recliner or chair is "dangerous and must be avoided," says McKenna, explaining that those situations are "very different from a breastfeeding mother sharing her bed with her infant because she wants to do so and she is informed as to how to make her bed safe."

Related: Dangers of co-sleeping with kids

He stresses that both adult sleeping partners need to be on the same page and suggests discussing with your partner "that they too take responsibility for the baby being there with them and go to bed with this thought in their head: 'Be careful, baby on board' or 'baby in bed.' This changes the level of sensitivity of all of us."

McKenna also distinguishes between bed sharing with babies who are breastfed and with those who are bottle-fed with formula. In his guidelines for safe co-sleeping, McKenna notes that "breastfeeding significantly helps to protect infants from death, including deaths from SIDS/SUDI [sudden unexpected death in infancy]." (In fact, research shows that breastfeeding for at least two months cuts the risk of SIDS almost in half.) But he adds that bottle-fed babies "should always sleep alongside the mother on a separate surface rather than in the bed."

When it comes to bed sharing safely, McKenna says, "Being informed is critical. When bed sharing is proactive, it makes mothers and infants happy, and that counts," adding, "Bed sharing is easier for mothers to breastfeed."

But Dr. Harvey Karp, pediatrician and author of The Happiest Baby on the Block, tells Yahoo Life that even though "there are some who say you should [bed-share] because of breastfeeding, that's nonsense." Karp continues: "Have the baby right next to you [such as] in a co-sleeper, and you can breastfeed as much as you want. We want to encourage breastfeeding — that's important for babies' and mothers' health, if a woman can do it. We want to give the best chance possible, but not at the risk of the baby's life."

Karp explains that studies have shown that "when you're sleep-deprived — which of course most parents are sleep-deprived — you're the equivalent of drunk." He points to research that shows a single night of missing one or two hours of the recommended seven hours of sleep "doubles your risk of a car accident." He says, "It goes without saying you shouldn't sleep with a baby if you're drunk, so why would you do it if you're sleep-deprived?" Karp adds that bed sharing with infants is "not something that's recommended," and "the reason is really straightforward — it's a higher risk for the baby."

That said, not every parent intentionally shares their bed with their baby. The AAP acknowledges that "even though it is not recommended that infants sleep on the same surface as the parents, there are times when parents may fall asleep while feeding their infant." It adds, "Evidence suggests that it is less hazardous to fall asleep with the infant in the adult bed than on a sofa or armchair, should the parent fall asleep."

The organization also points out that the risk of bed sharing with infants goes up the longer it lasts. So if a parent falls asleep while feeding an infant in bed, "the infant should be placed back on a separate sleep surface as soon as the parent awakens."

While the risk of SIDS goes up when infants sleep in the same bed as their parents, the risk actually goes down when an infant sleeps in the same room as the parents, according to the Mayo Clinic. In fact, the AAP encourages parents to have their infants sleep in the same room, "close to the parents' bed but on a separate surface," such as in a crib, portable crib or bassinet for at least six months but "preferably" a year.

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