Massive Study Suggests Breastfeeding Reduces Risk of SIDS

Breastfeeding babies for at least two months cuts their risk of Sudden Infant Death Syndrome almost in half, according to a large international study. Interestingly, the findings suggest that mothers need not exclusively breastfeed to reap the benefits of reduced risk.

“The peak age of SIDS is two to four months, so breastfeeding may need to continue into this apparently more vulnerable period to incur the protective effect,” study coauthor John Thompson of the University of Auckland told Reuters.

READ MORE: The Fatherly Guide to SIDS

This is not the first study to suggest that babies who are breastfed are less likely to die from SIDS—research from 2009 demonstrated that breastfeeding reduces the risk of SIDS by 50 percent. But that study was relatively small (333 victims of SIDS and 998 “control” infants) and the data did not provide much information about how long a mother had to breastfeed or whether she had to breastfeed exclusively to reduce her child’s risk. Indeed, a 2011 literature review of 288 studies suggested that this effect may be stronger when women breastfeed exclusively.

For the current study, published in Pediatrics, Tanabe and colleagues analyzed data from eight international studies that included 2,259 infants who died of SIDS and 6,894 healthy control infants. The results indicated that mothers who breastfed for at least two months protected their babies from SIDS, and that breastfeeding for fewer than two months produced no observable benefit. Surprisingly (and at odds with the 2011 study) the results also suggest that breastfeeding reduces the risk of SIDS even when it is not performed exclusively during that two month period.

“Any amount of breastfeeding [as long as it is done for two months] reduces the risk of SIDS,” study coauthor Fern Hauck, a physician at UVA Children’s Hospital, said in a statement. “In other words, both partial and exclusive breastfeeding appear to provide the same benefit.”

Some experts suspect that breast milk may strengthen babies’ immune systems and lower their risk of infections that could lead to SIDS. Others believe that the risk reduction has something to do with close contact with mothers during their most vulnerable period. Of course, it’s also possible that the risk reduction is a correlation that has nothing to do with causation. Perhaps women who breastfeed are more affluent and can afford to take longer maternity leaves, in which case the SIDS risk reduction would simply reflect the general trend that rich kids are less likely to die than poor ones.

“Parent behaviors are paramount in preventing SIDS,” Ian Paul of Penn State College of Medicine (who was not involved in the study) told Reuters. “Breastfed infants are likely to have more sustained and frequent interactions with their parents during the night at the key ages when SIDS is most likely to occur.” Study coauthor Kawai Tanabe of the University of Virginia School of Medicine said in a statement that this adds to the many reasons to promote support mothers nursing efforts worldwide—not just to reduce SIDS risk, but the risks of many other infectious diseases as well.

“Breastfeeding is beneficial for so many reasons, and this is really an important one.”