The science behind the AAP’s safe sleep recommendations
The AAP’s updated policy statement on safe infant sleep was released this week (1). I wrote a brief article about the policy update for the Washington Post, but I wanted to dig into the science a bit more in a blog post.
As a side note, let me just say that the opportunity to write for larger media outlets is very exciting, but also very humbling. A typical blog post for me is 2000 words, but I was asked to write 500-800 for the Post. It’s really hard to include in-depth science in a piece like that, but it’s something that I will keep working to improve. Still, can you imagine how I cringed when someone commented on Facebook, “Where is the science?!” about my article? But I probably would say the same thing, and I know that many readers want to understand the evidence base behind these recommendations.
The updated policy statement represented a 2-year effort by the AAP’s Task Force on SIDS to review literature published since the last policy statement, issued in 2011. The statement includes advice on how to reduce the risk of SIDS and other sleep-related deaths such as suffocation and asphyxiation, together considered sudden unexpected infant deaths, or SUID. It is often very difficult to determine whether SIDS or accidental causes caused a death, even after a thorough investigation, and many of the risk factors for these types of deaths overlap. About 3,500 infants die of sleep-related SUID in the U.S. each year. As a parent, I know that losing one of my babies during sleep was one of my greatest fears, and that number holds an incomprehensible amount of tragedy and grief for families. The goal of these guidelines is to prevent those deaths.
The AAP’s Task Force on SIDS is a group of 5 pediatricians, most of them having spent their careers studying SUID. For this 2016 revision, the Task Force also included breastfeeding researcher Lori Feldman-Winter. She told me that she was invited to the Task Force specifically to bring more research and perspective on breastfeeding to the group and to help address the controversy around the risks of bedsharing by breastfeeding mothers (more on that in a minute). The policy statement was also reviewed by the AAP’s Section on Breastfeeding. “The final product is really a meeting of the minds so that we can feel good about what we’ve put forth as the best evidence and the recommendations that follow,” Dr. Feldman-Winter said.
The policy statement is accompanied by a technical report that is loaded with science (400 citations), and it can be accessed and read by anyone interested (2). It’s a tough job for the AAP to issue recommendations for an entire population, knowing that there are big differences in cultural practices and real-world experience, but my opinion is that these recommendations are thoughtful and evidence-based and represent the Task Force’s best advice for parents.
Many of the recommendations on SUID prevention remain the same and should be familiar to parents, although they always bear repeating. Place babies on the back for every sleep, never on the stomach or side. Babies should sleep on a firm, flat surface with no loose bedding, pillows, or toys. Breastfeeding, immunizing on schedule, and getting regular prenatal care all reduce the risk, as does avoiding exposure to cigarettes, alcohol, and drugs in pregnancy and after birth. I’ll put the full list of recommendations at the bottom of this post, but I’ll use the rest of this post to take a closer look at the science behind the recommendations that have received the most attention in the past few days.
Babies should sleep in the parents’ room, close to the parents’ bed, ideally for the first year of life but at least the first 6 months.
Roomsharing without bedsharing was also recommended in the AAP’s 2011 policy statement, but they didn’t specify how long this arrangement should last. I think many parents overlooked the roomsharing recommendation in the past, but this revision gives it new emphasis. Roomsharing for 6-12 months is also recommended in other countries, including the U.K. and Australia.
Studies have shown roomsharing without bedsharing to be protective against SIDS since at least the mid-1990’s. Here’s what I wrote about roomsharing in a blog post from last year:
One of the largest case control studies of SIDS combined data from 20 different regions of Europe, allowing researchers to look at 745 SIDS cases and the risk factors associated with them (3). The authors of this study estimated that 36% of SIDS deaths could have been prevented if infants weren’t placed for sleep in a separate room, and 16% could have been prevented if infants weren’t bedsharing. Together, this means that if all of the infants in this study had slept in the same room as their parents, but not the same bed, more than half of their deaths might have been prevented.
This same protective effect of roomsharing has been observed in several other case control studies conducted in Scotland, England, and New Zealand (4–6). The English study found a dramatic 10-fold increased risk of SIDS associated with babies sleeping in their own room. Importantly, at least one study has shown that when infants share a bedroom with other children, it is not protective.6 Instead, the presence of an adult caregiver seems to be important.
Why is room-sharing protective? We don’t know, but it is a strong and consistent effect. The running hypothesis (again from my previous post):
Babies sleeping in closer proximity to their mothers have more sensory exchange (from noises, a touch when a parent checks the baby, etc.) and thus spend more time in light sleep and have more short arousals that protect them from SIDS (5–7).
Most of the studies that have looked at roomsharing have just looked at all deaths under one year of age without trying to parse the data by age. One New Zealand study (6 published in 1996 found that roomsharing was equally protective in infants aged less than 13 weeks, 13-19 weeks, and 20 weeks and older. Without more evidence, the AAP couldn’t say that roomsharing becomes less important at any age, so they took the cautious approach of recommending it for the entire first year. (And caution is what we want when we’re talking preventing infant deaths, right?) They do note that most SIDS deaths occur in the first 6 months, so roomsharing is most important during this time.
It’s worth noting that most of our understanding of how to reduce the risk of SIDS and other sleep-related deaths come from case control studies or case series, observational studies that simply can’t distinguish causation from correlation. We’re limited to these types of study designs because, thankfully, SIDS is relatively rare, and it would be virtually impossible to conduct prospective cohort studies or randomized controlled trials on SIDS. The evidence on roomsharing can’t tell us for sure that it causes a lower risk of SIDS, just that it is correlated to a lower risk of SIDS. There could be a confounding factor here – something else that roomsharing parents are more likely to do – or it could be a true effect. Either way, in recommending roomsharing, the AAP is making the best recommendation that they can based on the best evidence that they have.
Evidence also shows that most parents in the U.S. are not roomsharing much beyond the first few months of life. A study published this August in Pediatrics found that among 160 Pennsylvania babies, 55% of 3-month-olds and 74% of 6-month-olds weren’t sharing a room with their parents. Several studies show that parents who roomshare–especially in later infancy–experience more disrupted sleep and are more likely to have stressed relationships with their partners (again, this is a correlation, not necessarily caused by roomsharing). Sleep training is also usually more successful when babies sleep in their own rooms. It will be interesting to see if the stronger roomsharing recommendation will create a cultural shift in sleep environments for babies.
Bedsharing is not recommended.
The AAP’s advice against bedsharing is probably the most controversial recommendation, in part because so many families do it anyway. For some, it is a cultural norm and for others, it is seen as a way of bonding with their babies and facilitating nighttime breastfeeding. Others find that they just struggle to get a reasonable night of sleep without bringing the baby into bed. Still, the AAP is reaffirming their stance that bedsharing is a risk to babies, based on the current evidence.
It’s very clear from decades of studies of SIDS and other sleep-related deaths that bedsharing is associated with many of these deaths. What is controversial is if it is bedsharing itself that is the hazard or if it is other circumstances that might accompany bedsharing – soft mattresses, loose bedding, drug or alcohol use, or sleeping on a sofa or armchair.
Two studies addressing this question were published since the AAP’s 2011 policy statement, but they came to contradictory conclusions. A 2013 study led by Bob Carpenter concluded that, in the absence of these other risks, bedsharing still increased the odds of dying of SIDS by 2.7-fold, and in breastfed babies younger than 3 months old, the odds increased to 5-fold compared to babies roomsharing without bedsharing. However, this study was criticized for lacking much real data on parental drug and alcohol use. And then, a 2014 study led by Peter Blair found that the risk of SIDS wasn’t significantly increased with bedsharing in the absence of other risks, even in younger babies.
Given this conflicting evidence, the AAP commissioned a biostatistician who is not invested in this field to review these two studies. His conclusion? Both of these studies were small, and both had limitations. They used different control groups, which may have pushed Blair’s study towards underestimating the risk and Carpenter’s study towards overestimating the risk, so the real risk may lie somewhere in between. Given this uncertainty, Feldman-Winter said, “we can’t, based on the available evidence, rule out the fact that there is a hazard to bedsharing.”
The AAP notes that some situations make bedsharing more dangerous: when either or both parents are smokers, including if the mother smoked in pregnancy; with babies who were born preterm or low birth weight; in babies less than 4 months old; with any alcohol or illicit drug use that might impair arousal; when there are multiple bedsharers, especially if one of them is not a parent (including other children or pets). Bedsharing on very soft surfaces such as waterbeds, sofas, or armchairs is exceptionally dangerous, and loose bedding or pillows further increase the risk.
But, if parents fall asleep while feeding their babies, it is safer for this to happen in a carefully arranged bed than on a couch or chair.
This is a nuanced but important change in the AAP’s advice. The 2011 policy statement also advised that parents should not sleep on a couch or a chair with a baby, but anyone who has been through the early infancy period knows that there is a good chance of this happening at some point. “I think that what people really wanted after the last policy statement was recommendations on what to do,” said Dr. Feldman-Winter.
So, this time around, the AAP states that if you are in this precarious situation where you know that you may fall asleep while you feed your baby, that it is safer for that to happen on a carefully arranged bed than on a couch or chair.
A 2014 case series published in Pediatrics found that 1,024 infants died while sleeping on a couch or armchair in the U.S. between 2004 and 2012.8 These are preventable deaths. Other studies have found that sleeping with an infant on a couch or chair increases the risk of death by as much as 50- to 60-fold, many times the risk of bedsharing.4,5
If you do feed your baby in bed, arrange it to be as safe as you can. “We also make recommendations about keeping the bed as risk-free as possible by removing pillows and blankets and loose sheets and loose bedding, and also having a firm mattress,” said Dr. Feldman-Winter.
Ideally, the AAP says, you place your baby back in their own bed once you’re done feeding. If you fall asleep, you move your baby as soon as you awaken. I like Elissa Strauss’s suggestion at Slate on this: involve your partner by asking him or her to set an alarm for each feeding and help you move the baby should you both fall asleep.
You don’t need fancy monitors or devices or mattresses to create a safe sleep environment for your baby.
Here’s what Dr. Moon told me about creating a safe place for your baby to sleep: “You don’t need much to prepare a safe sleep environment for your baby. You want a flat, firm surface, and by firm I mean hard…. Ideally a crib, a portable crib, a playpen, or a bassinet. You want the mattress to be fitted for that device. You want a tight-fitting sheet. And then you just want the baby. You don’t want anything else in the crib, so bare is best. Ideally, we want the sleep place to be in the parents’ room, close to the parents’ bed.”
There are a ton of other products out there that promise or imply that your baby will sleep better or be safer if you use their device. There is no evidence that any device can reduce your baby’s risk of SIDS. None. Not the breathable mattresses, which I wrote about for Slate. Not the Rock n’ Play. Not baby swings or carseats. The market for infant care products is largely unregulated, Dr. Moon told me, and there is not a formal process for testing these products for safety. We generally don’t know that a product is hazardous until it causes injuries or deaths and a recall is issued. So, stick with a basic firm, flat, blanket and bedding-free bed for your baby.
Expensive monitors that track your baby’s vital signs also have not been shown to keep babies any safer when they sleep, and pediatricians worry that they might give parents a false sense of security. “I’ve heard many times that if I buy a $500 monitoring device, I don’t have to do the other sleep guidelines, that my baby can sleep prone [stomach down] because they have a pulse oximeter on them all the time,” said Kansas City pediatrician Dr. Natasha Burgert. “They think, I’m exempt from those other suggestions, because I have outsmarted the system by using this technology.”
Pediatricians should have non-judgmental conversations with parents about sleep safety
This is an important addition to the policy statement. Why? Because I know from experience that it can be hard to follow every safe sleep recommendation every night with a young infant, even when you are well-educated about the risks. Sleep is a biological need, and sleep deprivation also has very real risks. Parents are often making decisions in desperation, but a better approach is to rationally weigh risks and benefits and make a plan for sleep that reduces the risks as much possible. Pediatricians can be a great resource in that conversation, and if you’re concerned about sleep, they should be able to help you move towards better, safer sleep for your family.
Here is the full list of safe sleep recommendations from the AAP’s 2016 policy statement:
- Back to sleep for every sleep.
- Use a firm sleep surface.
- Breastfeeding is recommended.
- Room-sharing with the infant on a separate sleep surface is recommended.
- Keep soft objects and loose bedding away from the infant’s sleep area.
- Consider offering a pacifi er at naptime and bedtime.
- Avoid smoke exposure during pregnancy and after birth.
- Avoid alcohol and illicit drug use during pregnancy and after birth.
- Avoid overheating.
- Pregnant women should seek and obtain regular prenatal care.
- Infants should be immunized in accordance with AAP and CDC recommendations.
- Do not use home cardiorespiratory monitors as a strategy to reduce the risk of SIDS.
- Health care providers, staff in newborn nurseries and NICUs, and child care providers should endorse and model the SIDS risk-reduction recommendations from birth.
- Media and manufacturers should follow safe sleep guidelines in their messaging and advertising.
- Continue the “Safe to Sleep” campaign, focusing on ways to reduce the risk of all sleep-related infant deaths, including SIDS, suffocation, and other unintentional deaths. Pediatricians and other primary care providers should actively participate in this campaign.
- Avoid the use of commercial devices that are inconsistent with safe sleep recommendations.
- Supervised, awake tummy time is recommended to facilitate development and to minimize development of positional plagiocephaly.
- Continue research and surveillance on the risk factors, causes, and pathophysiologic mechanisms of SIDS and other sleep-related infant deaths, with the ultimate goal of eliminating these deaths entirely.
- There is no evidence to recommend swaddling as a strategy to reduce the risk of SIDS.
What questions do you have about prevention of SIDS and other sleep-related deaths?
- AAP’s Task Force on Sudden Infant Death Syndrome. SIDS and Other Sleep-Related Infant Deaths: Updated 2016 Recommendations for a Safe Infant Sleeping Environment. Pediatrics e20162938 (2016). doi:10.1542/peds.2016-2938
- Moon, R. Y. & AAP’s Task Force on Sudden Infant Death Syndrome. SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment. Pediatrics e20162940 (2016). doi:10.1542/peds.2016-2940
- Carpenter, R. G. et al. Sudden unexplained infant death in 20 regions in Europe: case control study. Lancet 363, 185–191 (2004).
- Tappin, D., Ecob, R. & Brooke, H. Bedsharing, Roomsharing, and Sudden Infant Death Syndrome in Scotland: A Case-control Study. J. Pediatr. 147, 32–37 (2005).
- Blair, P. S. et al. Babies sleeping with parents: case-control study of factors influencing the risk of the sudden infant death syndrome. Br. Med. J. 319, 1457–1462 (1999).
- Scragg, R. K. et al. Infant room-sharing and prone sleep position in sudden infant death syndrome. New Zealand Cot Death Study Group. Lancet Lond. Engl. 347, 7–12 (1996).
- McKenna, J. J., Ball, H. L. & Gettler, L. T. Mother-infant cosleeping, breastfeeding and sudden infant death syndrome: what biological anthropology has discovered about normal infant sleep and pediatric sleep medicine. Am J Phys Anthr. Suppl 45, 133–61 (2007).
- Rechtman, L. R., Colvin, J. D., Blair, P. S. & Moon, R. Y. Sofas and Infant Mortality. Pediatrics 134, e1293–e1300 (2014).