With all the expensive safety products marketed to new parents -- baby-safe furniture, strollers with mosquito nets and BPA-free bottles -- researchers have found that using a simple fan in the bedroom can also save lives.
Having a fan running near a sleeping infant was associated with a 72 percent decrease in the risk of sudden infant death syndrome, or SIDS, researchers reported in the Archives of Pediatrics and Adolescent Medicine.
"Obviously, further research needs to be done," said Betty McEntire, executive director for the American SIDS Institute in Marietta, Ga. "But I really commend these researchers because every new data we have on SIDS is a plus."
SIDS claims 2,500 babies a year in the United States. Doctors are still looking for a cause, and more ways to prevent it.
"At that time, nobody knew the fan would have such an effect," said Dr. De-Kun Li, a co-author of the study and a senior research scientist at the Kaiser Permanente Division of Research in Oakland, Calif.
"But at that time, we already knew that the sleep environment matters," said Li.
Doctors may not know what causes SIDS, but they have found that the "sleeping environment" contributes to it. Deaths from SIDS decreased by 56 percent from 1992-2003, after national "back to sleep" campaigns urged parents to put babies to sleep on their backs.
McEntire, who has worked on SIDS research since 1976, said only three simple steps have been shown to reduce SIDS: Don't smoke, don't put anything but the baby in the crib, and put the baby on its back.
To glean more information about sleeping environment and SIDS, Li and his colleagues analyzed 497 interviews with parents, 185 of whom lost a child to SIDS. The researchers found the link between fans and SIDS by crunching the numbers from the environments where babies survived, and the environments where babies were lost to SIDS.
Li said larger studies are needed to analyze the 72 percent risk reduction from fans, but that the finding fits with other well-known SIDS risk factors including whether the baby's head is covered by blankets and whether the child is co-sleeping with an adult in a bed.
"This finding (about fans) by itself is new, and it fits into other findings," said Li. "All those seem to be a piece of a puzzle that points to rebreathing, a leading hypothesis," said Li.
Many doctors hypothesize that "rebreathing" a pocket of stale air trapped in covers, sheets or beneath the baby can cause SIDS. According to the hypothesis, adults and older children do not suffer from rebreathing because they could move in their sleep before they suffocated.
"Their [newborn] neck is so weak, and their head cannot move, that they cannot struggle to regain the air, or the airway to get rid of this re-breathing," said Li.
Dr. John Kattwinkle, chairman of the American Academy of Pediatrics SIDS task force, found the study "interesting" but he sees a connection to temperature, not rebreathing.
"I'm not really sure if that's going to affect rebreathing," said Kattwinkle. "Probably, the fan going in the room is not going to diminish this."
However Kattwinkle, who is also a professor of pediatrics at the University of Virginia in Richmond, thought the finding fit better with past research that overheating is a risk factor, as well as the so-called arousal threshold.
"If the problem is arousal threshold being diminished, then this could help," said Kattwinkle, who explained that infants may be more likely to sleep lighter with a fan is blowing on them and would therefore be more likely to wake up if they're rebreathing.
"You just need to wait for confirming studies before you hang your hat on it," said Kattwinkle. "We don't want people to think that it's OK for the baby to sleep its stomach if you use a fan."