What position is the best for putting my baby to sleep? We know now that putting the baby on her back, on a firm surface, is the safest? But how do we know this? The famous “Back to Sleep” campaign did not appear out of thin air. It was the result of many years of careful study in the field of epidemiology. One tiny little change in our behavior, putting the baby down on her back instead of her belly, has saved millions of lives in the 20th century.
“Back to Sleep” campaigns came about as the result of the search for the causes of Sudden Infant Death Syndrome (SIDS). SIDS has also been called “cot death” or “crib death”.
In the US, unexplained sudden infant death is the #3 cause of infant mortality, after congenital malformations and extreme prematurity. But between the ages of 1 month and 1 year, SIDS is the #1 cause of death. The most common age for SIDS deaths is between 2-4 months of age.
Need a SLEEP COACH?
By definition, SIDS has no cause. For example, if an infant suffocates on a blanket in her crib, the cause is suffocation, not SIDS. We cannot make a diagnosis of SIDS unless a thorough forensic investigation and an autopsy has been completed. Only then, when no other medical or criminal cause has been found, can SIDS be given as the reason for death.
Because the causes of SIDS remain mysterious, researchers had to find other ways to figure out how to prevent it. The search began with a number of observations starting in the middle of the 20th century.
The Origins of Back to Sleep
In 1944, in an article entitled “Accidental mechanical suffocation in infants”, Dr. Harold Abramson suggested that someone ought to do a study to ask whether sleeping position had anything to do with infant deaths. It was not until the mid 1960’s and early 1970’s that these studies were actually done. Both showed that sleeping on the belly was associated with infants dying of SIDS. But it was not until 1986 that any researcher even suggested that infants sleep on their backs to reduce the incidence of SIDS. This study was done in Australia. The suggestion was taken up and SIDS rates began to go down. The United Kingdom and Denmark soon followed with their own campaigns, with positive results.
Several other interesting observations were made. The rate of SIDS is extremely low in Hong Kong, compared to the US. A well-done study of the the territory in 1985 showed that the most Hong Kong babies go to sleep on their backs.
Another carefully-performed study in Sweden showed that rates of SIDS went up and down as recommendations about infant sleeping position changed over time.
The US climbs on board
Finally, public health officials in the US began to pay attention to the mounting evidence. As you can see from the graph, the American Academy of Pediatrics started its back to sleep campaign in 1992. From that point on, an interesting thing began to happen: Rates of back sleeping began to increase (green dotted line), and rates of SIDS began to fall (red bars). This was a similar result to what had happened in other countries.
Causation is not correlation, but…
You always have to be careful when you look at studies like the ones mentioned here. It is always possible that the cause (putting baby on her back) and the effect (lowered SIDS rate) are not related to each other. This could be a coincidence. This is especially so because we still don’t know what causes SIDS. There’s a lot of speculation, but we just don’t know. What we can say is that all over the world, the same result has happened. Back to sleep campaigns get started and SIDS rates go down. If this is the case, we should be less concerned about what the true causes of SIDS are, because we appear to have found a way to prevent many cases of SIDS.
Keeping in mind that we don’t know what actually causes SIDS, there are a number of other risk factors that have emerged from these studies:
- Tobacco smoke: SIDS rates are higher for mothers who smoke during pregnancy
- Sleeping with a pacifier: This appears to lower the risk of SIDS
- Breastfeeding: Infants who breastfeed are at slightly lower risk of SIDS
- Genetics: Boys are more likely than girls to die of SIDS
- Vaccinations: These appear to be protective. Again, no one knows why
What to do about “flat head”?
There’s no question that it’s a very good thing that SIDS is so rare now, thanks to what we’ve learned. But there is one unintended consequence of all the back to sleep campaigns: flat head. Called “positional plagiocephaly“, it’s the result of, well, laying on the back while your baby head is growing rapidly. It’s occurring now in about 10-50% of all babies that sleep on their backs. Most babies who have a mild case of flat head will grow up to have a normally-shaped skull. The best way to reduce the amount of head flattening your baby has is to do observed “tummy time” about 20 minutes per day. It’s also recommended that you position the baby’s head alternatively to the right and to the left when she sleeps. This will help keep her most symmetrical. Do not use positioners. These are not recommended.
If you’re concerned about any of this, SIDS and/or flat head, please consult your pediatrician!