). It is this evidence that has lead agencies such as the American Academy of Pediatrics to have an official policy against bedsharing. And yet, despite what could be seen as overwhelming evidence, many people, myself included, read these articles and remained skeptical about the link between SIDS and bedsharing. But why?
As a researcher myself, I am always interested in both the quality of studies that I read, but also of the logic that stems from research. You pose a question, you design a study, and hopefully if all goes well, you’ve at least gotten closer to answering that question. But to do this, you must make logical assumptions. For example, suppose I want to see if A causes B. Inherent in this is the believe that it is A per se that causes B, not a correlate of A or some aspect of how A is done that leads to B, but A in and of itself. This is important because one must be aware of factors that can affect these relationships and account for them in one’s research whenever possible. It is this issue that allowed me to remain skeptical of the aforementioned research and the notion that bedsharing per se is not safe.
As previously mentioned, many individuals who believe bedsharing to be unsafe believe that it can never be safe, and proponents have written opinion pieces saying as much. The first red flag for this point of view is that there is ample anthropological evidence that we have evolved as a species (as other mammals have) to co-sleep with our offspring. Why does this matter? Because evolution doesn’t build features into our system that harm us, we can only remain neutral or be helped by what we have evolved to do when done in the way evolution intended. Those opposed to bedsharing have commented that we wouldn’t accept the infant mortality rate of our ancestors, and while true, it also is irrelevant as the vast majority of those deaths had nothing to do with bedsharing, but rather infection, malnutrition, etc. Another common response is that other mammals will overlay or suffocate their offspring. While I am willing to accept that this happens on occasion, I have yet to see a single piece of evidence that this is a significant problem amongst other mammals. I have searched for scholarly articles on the topic and found nothing which leads me to believe that while it may happen, it is not an epidemic and we need to weigh the times this might happen against what might happen if infants are not sleeping with a parent. What is often ignored by those who are opposed to bedsharing is that there is substantial evidence that children left in a crib in a room separate from their parents (the new ‘norm’ in Western society) is associated with a large increased risk for SIDS, even when bedding and mattress and temperature are taken into account. At the very least, I hope people see the need to keep babies close to their parents, even if not in the same bed.
Importantly, though, one aspect of the evolutionary argument is often ignored; “the way evolution intended” suggests we also need to be cognizant of how our environment has changed because changed it has and in a dramatically short span of time (evolutionarily speaking). Big, soft beds and fluffy pillows with duvets have hardly been the norm over the history of mankind and thus must be considered when we think of the safety of babies when bedsharing. This brings us to red flag number two –the studies that have found an increase in SIDS associated with bedsharing have failed to control for all of the known safety factors that affect safe bedsharing. While many have controlled for smoking and alcohol use (and once these are controlled for, the results with respect to SIDS and bedsharing are equivocal), they do not account for room/infant temperature, type of bedding, presence of pillows or duvets, overcrowding in the bed, etc., all of which have been implicated as risk factors for SIDS or suffocation when bedsharing. One study that examined these myriad factors with respect to bedsharing and SIDS found that bedsharing was a non-significant factor in predicting SIDS. In other words, it seems to be the way in which we now bedshare that poses an increased risk to infants, not bedsharing per se.
There’s a third red flag though, and one that is particularly salient. In order for individuals to claim that bedsharing is never safe, it has to hold across cultures and different practices, and yet today we have Japan. Japan boasts some of the highest rates of bedsharing (close to 40% bedshare on a regular basis) and yet some of the lowest rates of not only infant mortality, but SIDS specifically. The only rebuttal to this that I have found from anti-bedsharers comes from a quote in an article on SIDS and weather, done by researchers in Taiwan, and it is as follows:
Together SIDS and suffocation account now for 20% of the total infant mortality in Taiwan, representing a yearly rate of close to 1 per 1000 live births, a figure similar to infant mortality from SIDS alone in western countries. SIDS as a distinct diagnosis has recently been introduced because suffocation seemed an inappropriate diagnosis for the majority of sudden unexplained infant deaths. Suffocation as cause of death is now rarely recorded in western countries. The situation in Asia is essentially different. Taiwan and Japan both record suffocation rates that are higher than SIDS rates, and together these two causes of death sum up to values similar to those for SIDS in western countries. We include accidental suffocation diagnoses in SIDS, taking the view that from a western perspective both terms would be synonymous.
If this were the whole story, we might have to accept that there is something wrong with the Japan argument, but there are a couple major flaws in this statement. First, the separation of suffocation and SIDS may have previously occurred in Japan, but that has changed in recent times, as has been reported by SIDS researchers and educational advocates. In fairness, this article was written in 1995, but 16 years later, the understanding and diagnosis of SIDS is much better understood and utilized in Japan. And the rates continue to be low. The second flaw is that the statement that the rates in Japan are similar to those in Western countries is factually inaccurate. A study out of Japan on SIDS rates in the late 90s addressed the issue of suffocation vs. SIDS and included the rates of both of these forms of death from 1980 to 1999, as shown below:
By simply combining the numbers for the two, you still have lower rates of death than those in Western countries. For example, in 1990, the combined rate for Japan would be approximately 0.35 per 1000 live births compared to the US rate of approximately 1.3, a number much lower than Western countries. Furthermore, comparisons of rates that include both suffocation and SIDS continue to be much lower in Japan. Below is a graph from the National Sudden and Unexpected Infant/Child Death and Pregnancy Loss Resource Centre on 2005 rates of SIDS by country:
As you can see, the rates for Japan are at most half of many Western nations. If one is going to say that bedsharing per se increases the risk of SIDS, then we have a logical dilemma with the data from Japan.
I’ve also read statements from anti-bedsharing advocates that there is research showing bedsharing to be a factor in SIDS even in Japan, but with no citations to back that up. As I could only find one article stating anything remotely like this, I can only assume they refer to an article by Mukai and colleagues in Legal Medicine from 1999 which reports in its abstract: “In addition, the co-sleeping habit, which was not uncommon in Japan, seems to contribute to certain deaths of infants whose causes of death were controversial.” I can also only assume those who use this article to make any statement on bedsharing have yet to actually read it in full. First, there was no analysis conducted on co-sleeping as a factor, but rather a discussion of the potential role of co-sleeping in three particular cases. Second, these three cases all included elements of bedsharing which are considered unsafe – one mother was drunk and her leg was over two infants’ faces when they were found dead and in the third case the infant was found under an older sibling. Furthermore, the rates of bedsharing in the SIDS and control groups were comparable and the rate of SIDS for infants in the same bed as parents or next to the parent bed, but on their own bed, was virtually identical with rates of 23.4% and 21.4%, respectively. (It is worth noting that this study also included both SIDS and suffocation deaths together under the umbrella of “SIDS”.) Outside of this one study, I have yet to find any research suggesting bedsharing is an issue pertaining to SIDS in Japan, and in fact, one study found the opposite – that sleeping alone was a significant risk factor.
So we must now ask ourselves, what does Japan do that is different?
For starters, they have lower rates of maternal smoking and alcohol consumption than Western nations and that alone will significantly contribute to lowering the risk of SIDS while bedsharing. But their bedroom also contains fewer risk factors. Here’s an example (though stereotypical) of a traditional Japanese bedroom:
Note the important part is that the bed is low to the floor with few sheets, and nothing large and fluffy. There are few pillows, none large, and the mattress is firm. We can hope that the temperature remains at or near the optimal 68oF (though I’m sure it varies). Moreover, more Japanese women give up their jobs to stay at home to raise their children, meaning they aren’t juggling work and childrearing and thus are not as sleep-deprived as their Western counterparts. Compare this with Western nations where women smoke and drink in larger proportions, our beds are soft and high off the ground, we use duvets and lots of pillows, we set temperatures that are much hotter than they need be for sleep, and we have people back at work after just weeks after giving birth. In fact, many mothers in the US decide to bedshare to get more sleep because they are exhausted. The very fact that they are overtired is one reason why they should not be bedsharing at that particular point and poses a problem in research as it is a factor that is often overlooked. It is also for these reasons that larger agencies, such as the American Academy of Pediatrics, speak out against the practice. It’s not that all doctors believe bedsharing to be unsafe period, but rather there’s the proverbial covering their asses that has to take place, and as long as we live in a society whereby our norms remain distinctly different from what is necessary to bedshare, how can they be expected to make blanket statements in support of it? From a policy point of view, you have to do both what is best for the masses and easiest to implement, and with the list of don’ts that accompany bedsharing, is it any wonder these groups oppose the practice publically?
If we take all of this together, I hope a clearer image starts to appear. Namely, that the claim that bedsharing is never safe is rather disingenuous. It can and has and continues to be done safely around the world. But – and there is a ‘but’ – there is a problem in Western countries in that safe bedsharing is not being practiced by many. Women are sleeping with their babies on sofas (one of the largest contributors to infant sleeping deaths in one UK study), sleeping while overtired, drinking, smoking, etc. and these are all putting their infants at greater risk for death. It is a problem that we need to take seriously, but as I have stated before, I do not believe we simply abandon the practice of bedsharing altogether or threaten families with criminal action for parenting in a way that is responsive to their baby biologically and historically. I liken it to safe sex education: If you only preach abstinence then those who will do otherwise (for many reason) will not have the information to keep themselves and others safe, but if you speak of the benefits of abstinence and acknowledge it won’t work for everyone and then teach safe sex on top of it, well, you’re making sure more people are safe. (And of course the fallacy in this analogy is that cot sleeping is “risk-free” like abstinence, but we know that’s not the case either. SIDS used to be known as cot-death and babies in their cots in their parents room still die of SIDS.)
It may not be for everyone, and there are those who simply should not bedshare (like smokers), and in these cases, we need to be promoting room-sharing over the now common practice of placing a baby in their own room, separate from mom. Indeed, some people room-share for the first few months where the SIDS risk is greatest and then bedshare once the infant is old enough and strong enough to move around better whereas others just never bedshare. But for those who want to bedshare from the start or who have an infant who will not sleep without mom, learning how to safely bedshare is a must, and an area in which more education is sorely needed. Safe bedsharing is not a myth and it is not out of reach, but it does require education and work.
[Photo/Image credit: Gioia Albano]
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