Baby sleep

Safe sleep for babies

A thinking parent's guide to safe sleep advice

By John Hoffman
Safe sleep for babies

Advice about safe sleep for babies is nothing new. But it sure has changed. Twenty-five years ago, doctors advised parents to put their infants down on their tummies to avoid the possibility of choking on milk or spit-up. Experts were starting to address crib safety issues, such as ensuring crib bars weren’t too far apart. But nobody had much advice for parents on how to prevent sudden infant death syndrome (SIDS), the tragic incidents where babies die mysteriously in their sleep.

Today, over 20 years of studies have identified numerous risk factors for SIDS resulting in a long list of safety guidelines for parents.

Here is the current advice: Parents are told to place the baby on his back in a crib that meets Health Canada standards, preferably in the parents’ room until the baby is six months old. Sharing a bed with your baby is risky, some experts advise, but having the baby near you protects against SIDS. And, in contrast to the days when cribs were festooned with lush decorative duvets, bumper pads and a stuffed animal or two, today’s baby crib is supposed to be empty except for your baby and perhaps one light, tucked-in blanket. Some advice givers don’t even approve of the blanket. One Canadian parenting website illustrates its safe sleep article with a photo of an empty crib bearing the caption: “No toys, no blankets, no drapes, no bumper pads, no anything.”

Finally, the room should not be too warm, and baby’s environment should be smoke-free.

Not much when you say it fast! Some of this advice has been well accepted (for example, most parents now put babies on their backs). But other advice, particularly advice against bed sharing, has been controversial.

Long lists of safety rules are not only complicated, they have the effect of making it seem as if all risks are equally important. That is not true in the world of safe sleep advice. According to paediatrician and SIDS researcher Aurore Côté, of McGill University in Montreal: “The most important risk factors are smoking during pregnancy, sleeping on the stomach (for the baby) and co-sleeping (bed sharing) in certain situations — on a sofa, if the parents have been drinking or using drugs, or on a makeshift bed with pillows and cushions. None of the other risk factors are nearly as important.”

Here’s a guide to help you understand where today’s safe sleep instructions come from, why some are more important than others, and whether some lesser risk factors might be relevant to you.

Back to sleep

Putting babies to sleep on their backs has been better publicized than any other piece of SIDS prevention advice. In the late ’80s and early ’90s, research began to show an association between SIDS and prone (on the tummy) sleeping. In North America, the US Back to Sleep campaign was launched in 1994. The effect was substantial: The percentage of babies sleeping on their stomachs fell from 70 percent in 1992 to 13 percent in 2004. In roughly the same period, the SIDS rate was cut in half. In England’s Avon County, they’ve kept meticulous SIDS records since 1985. Their rate of cot death (as they call it in the UK) has dropped tenfold, according to Peter Blair, a medical statistician and senior research fellow at the University of Bristol who has co-authored several studies based on data from Avon. Some of that drop is due to changes in the way they diagnose SIDS (see Understanding risk), but still it’s hard to argue with the evidence that back sleeping saves lives.

The bottom line: Put your baby on her back for sleep from birth. At one point, experts were saying that side sleeping and back sleeping were equally safe, but more recent research shows that the biggest reduction in risk is from back sleeping. That’s because it’s relatively easy for a side-sleeping baby to roll onto her stomach. The only reason for a baby not to sleep on her back would be due to certain health conditions (your doctor will advise you), or when she gets to the age when she can roll over onto her tummy by herself and seems to prefer that. By then, babies have passed the main risk period for SIDS, which is one to three months of age.

Some experts in the field are beginning to suggest that regular tummy time (putting a baby on her tummy a couple of times a day during wakeful periods) may help back-sleeping babies develop the ability to move their neck from side to side. This may reduce the risk if they happen to roll over onto their tummies during the night.

What about a baby who doesn’t sleep well on her back? Tough question. If you feel that your baby simply cannot sleep on her back, it’s best to talk it over with a health professional who can help you assess all of the SIDS risk and protective factors that apply to your baby, along with your family’s need to get enough rest.

 Smoking: The big risk factor

With the success of the Back to Sleep campaign, the single most important modifiable SIDS risk factor is now parental smoking. The Avon County study showed that 86 percent of SIDS deaths now occur in babies whose mothers smoked during pregnancy. Exposure to second-hand smoke in the first months of life also increases the risk; however, many parents already know that they should not smoke around young children. They may not be aware that smoking during pregnancy is even more strongly associated with risk of sudden infant death. “We really can’t emphasize the risk of smoking enough,” says paediatrician Denis Leduc, an associate professor at the McGill University Health Centre and lead author of the Canadian Paediatric Society’s position paper on safe sleep in infancy.

The bottom line: If you or your partner are smokers, don’t panic — but get help to quit. Second-hand smoke is harmful for anyone, particularly young children. If you are unable to quit, at least don’t smoke in your house or in any room where the baby is. Don’t let anyone else smoke around the baby either. And understand that if you smoke, every other risk factor is multiplied, so you really do need to pay attention to all aspects of safe sleep advice. Bed sharing, for example, has been shown to be risky primarily when parents smoke.

The bed sharing controversy

Newspaper headlines in recent years might give you the impression that bed sharing is the biggest risk factor for SIDS. For example, in June 2007, the deputy chief coroner of Ontario strongly condemned all bed sharing, insisting that the only safe place for an infant to sleep was in an empty crib that meets regulations and has a tight-fitting mattress. The Canadian Paediatric Society is more flexible. They merely say that adult beds are not the safest sleeping place for babies, and go on to outline situations when bed sharing is most risky — on sofas or waterbeds, or when parents smoke or have been using alcohol or drugs.

Lots of parents share a bed with their babies. For some, it’s part of their parenting philosophy. For others, it’s a convenience. Breastfeeding advocates have pointed out that bed sharing can enhance breastfeeding (there is research to support this) and argue that sweeping edicts against bed sharing are uncalled for.

The truth, according to Blair, one of the world’s top SIDS risk researchers, is that the risk factor is not bed sharing but how it’s done. “Some cultures where co-sleeping is very common, like Japan, China and the Indo-Pakistani community in England, have some of the lowest SIDS rates in the world.” In the Western world, the incidence of bed sharing has increased during the same period that the incidence of SIDS has declined.

Blair’s research has revealed a recent spike in SIDS deaths that take place while a parent and baby are sleeping together on a couch. He’s not sure why, but he hopes parents are not hitting the couch with a fussy baby because they’ve been told not to take the baby into bed with them. “If you have to choose between sleeping with a baby on a bed or a sofa, take the bed every time,” says Blair.

The bottom line: Bed sharing is risky in the context of other risk factors, especially smoking, alcohol and illegal drugs. If you’re a non-smoking, sober breastfeeder with a fairly firm mattress (not a waterbed), and you take sensible precautions to make sure your baby is protected from falls, getting her head covered by blankets or pillows, and getting wedged between the mattress and bed frame or walls, whether or not you share a bed with your baby is your call.

 Room sharing

Several studies have shown that babies who died of SIDS were less likely than other babies to have slept in a crib or bassinet in their parents’ room on the night they died. And since, unlike bed sharing, the idea of room sharing is not controversial, it was easy to advise parents to have babies in their room for the first six months. However, it’s unclear how much protection room sharing actually provides. The studies showed that only about half of parents of non-SIDS babies room-share on any given night.

The bottom line: If a crib or newborn bassinet fits in your room, go for it. But if your bedroom space is limited, room-sharing is not important enough to warrant a renovation or moving house.


Many experts believe that breastfeeding probably reduces the risk of SIDS, but the evidence has been too ambiguous to draw firm conclusions. However, in a recent German study babies who died of SIDS were much less likely to have been breastfed than healthy babies in a control group. The authors concluded that breastfeeding reduced the risk of SIDS by 50 percent.

The bottom line: For a small number of babies, breastfeeding probably does reduce the risk of SIDS, but there are more important reasons to breastfeed.

Crib accessories

Bumper pads The risk with bumper pads is primarily suffocation rather than SIDS. Some babies have been found with their faces wedged in where the bumper pad meets the mattress. The numbers are small, but authorities recommend against bumper pads because they see them as unnecessary. There are reports of babies getting hurt when an arm or leg got caught between the crib bars, but experts say the risk of SIDS outweighs this concern.

Duvets, pillows and stuffed toys Some babies who died of SIDS were found with their heads covered. That led to the advice to avoid duvets, heavy blankets and even, according to some experts, any blanket at all.

The biggest risk factor with other “soft furnishings” is a cluttered crib. Death scene investigations have found that many sudden infant deaths take place in cribs with a lot of stuff in them.

The bottom line: What is most important is that the crib is not overcrowded. But it makes sense to follow the expert consensus to keep pillows and stuffed toys out of the crib. Your baby doesn’t need them and she doesn’t need a big duvet either.

 Overheated rooms

Earlier studies showed an association between overheating and risk of SIDS, but temperature (as long as it’s reasonable) is no longer considered a particularly important risk factor, partly because manufacturers are making lighter crib duvets.

The bottom line: If the room temperature feels comfortable to you, it’s fine for your baby.

The big picture

Please understand that nothing anyone can advise will prevent all SIDS deaths. And as you think about safe sleep advice and what you’ll do with it, remember the most important statistic of all: The number of SIDS deaths has been reduced dramatically and it keeps going down. Even though you hear much more than your mother did about how to prevent sudden infant death, you actually have far less reason to worry.

Understanding risk

When discussing SIDS risk factors, it’s important to keep two things in mind:

• Risk factors have been identified by comparing the circumstances and environments of babies who died of SIDS with those of healthy babies. Except in documented cases of smothering or other accidents, the risk factor is not the actual cause of death. SIDS is still a sad mystery, but most experts think the cause is some sort of vulnerability within the baby, such as a nervous system problem affecting the baby’s ability to rouse herself. The risk factor may interact with this physiological vulnerability, but nobody knows exactly how or why.

• The risk of sudden infant death is already very small. In Canada, the SIDS rate has been dropping steadily for the past 20 years. However, some of the reduction in SIDS statistics is due to changes in criteria. When medical examiners in some jurisdictions deem an infant’s death to have taken place in an unsafe sleep environment, they no longer call it SIDS.

This article was originally published on Aug 04, 2009

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