TUESDAY, Dec. 13 (HealthDay News) -- Babies who are born
prematurely are known to be at higher risk for Sudden Infant Death
Syndrome (SIDS), and new research now suggests that's because their
underdeveloped nervous systems can't control drops in blood
pressure as needed during sleep.
SIDS is the sudden, unexpected death of an apparently healthy
baby. The national Back-to-Sleep campaign, which encourages parents
to place infants on their backs to sleep, has dramatically reduced
the prevalence of SIDS. Still, more than 2,300 babies aged 1 month
to 1 year die from SIDS in the United States each year, according
to First Candle, a nonprofit group that raises awareness about
In this latest study, Australian researchers conducted sleep
testing on 25 preemies who were born at 28 to 32 weeks and 31
infants who were born full-term (between 38 and 42 weeks). They
found that the baroreflex -- the system that regulates blood
pressure -- does not mature as quickly in babies who are born too
early. As a result, the baroreflex may not be able to compensate as
quickly when there is a drop in blood pressure.
"Infants die during sleep because they fail to respond appropriately to a life-threatening situation such as a fall in blood pressure," explained study author Dr. Rosemary Horne, deputy director at the Ritchie Centre at the Monash Institute of Medical Research in Victoria, Australia.
Normally, "if there is a fall in blood pressure, heart rate will
increase and the blood vessels will constrict to raise blood
pressure," she said. "Conversely, if there is a surge in blood
pressure, heart rate will fall and the blood vessels dilate to
reduce blood pressure again."
But, this mechanism may not kick in as quickly in preemies, she
said. There is no way to speed the maturity of this mechanism, but
there are other things parents can do to help lower a premature
infant's risk of SIDS, she said. These include placing the baby to
sleep exclusively on his or her back, breast-feeding if possible
and avoiding exposure to cigarette smoke. "It is particularly
important that young babies are not sleeping with parents in the
parental bed or on a sofa, as evidence now shows these practices to
be significant risks for SIDS."
The study appears online Dec. 12 and in the January 2012 print
Dr. Rachel Y. Moon, director of academic development for the
Goldberg Center for Community Pediatric Health at Children's
National Medical Center in Washington, D.C., said that "preemies up
to six months of age may be at higher risk for SIDS because their
baroreflex is not as good and not as stable."
Do your best to eliminate any SIDS risks that are within your
control, said Moon, who is a national expert on SIDS. "It is
critical to try to give these babies every advantage they can get,"
she suggested, which includes placing them on their backs to sleep
on a firm surface without blankets or anything that will cover
their face. "Don't use pillows or bumper pads," she said.
"Sometimes parents think they are doing the right thing, but they
are unintentionally placing their infant in a more dangerous
situation by surrounding him or her with pillows to keep them
First Candle has more on