A recent reanalysis
of several past studies indicates a connection to breastfeeding and a lowered risk of death due to sudden infant death syndrome (SIDS).
The researchers cannot prove conclusively that breastfeeding causes the decreased risk of death by SIDS, but the authors of the study wrote that they found other explanations unlikely.
SIDS, also known as "crib death," is when a sudden and unexplained death occurs in a baby younger than one year old, most commonly seen in infants between two and four months old. According to the National Institutes of Health, SIDS is responsible for the deaths of nearly 2,500 infants in the U.S. annually.
While the cause of SIDS is still unknown, certain factors are associated with increased risk, such as minor infections, a baby sleeping on its stomach, or becoming overheated; also, SIDS is more prevalent in African American and male babies.
Dr. Fern Hauck of the University of Virginia School of Medicine in Charlottesville led the study. Hauck and her colleagues reviewed collective date from eighteen studies of mothers of infants who had or had not died of SIDS. The studies asked all mothers whether or not they had breastfed their infants.
After reviewing the findings, the researchers discovered that the rate of SIDS was 60% lower in infants who had received any amount of breastfeeding in comparison to infants who had not received breastfeeding.
Further, the risk of SIDS was over 70% lower in infants who had been breastfed exclusively, without receiving any formula.
The connection between breastfeeding and lowered risk of SIDS remained even when the authors took into account the fact that women who smoke cigarettes are less likely to breastfeed, and also may be more likely to have an infant die from SIDS. "We found a protective effect even after controlling for factors that could explain the association," Hauck said.
The authors said that one possible theory is that breastfeeding lowers the risk of SIDS because it provides infants with protection against minor infections thought to be one cause SIDS. The World Health Organization encourages mothers to breastfeed their infants for the first six months of life.
Along with breastfeeding, two other factors were found to lower the risk of SIDS: infants who slept in the same room but not in the same bed as their parents, as well as infants who used a pacified while sleeping both had lowered risk of death by SIDS.
Hauck acknowledged that the analysis did not conclusively prove a cause and effect relationship between breastfeeding and SIDS risk, but she said she is "fairly confident" that was the case here.
The authors and Hauck noted that they would like to do more research in order to determine if the duration of breastfeeding affects the risk of SIDS. Most especially, they said, they would like to see if babies who are breastfed for longer periods of time receive more protection against SIDS than babies who are breastfed for a shorter period of time.
"Breastfeeding is the best method of feeding infants," said Hauck.
This study is published in the journal Pediatrics