SIDS vulnerability
August 29, 2008
Premature babies of mothers who smoke particularly vulnerable to SIDS
New research at the University of Calgary shows premature infants whose mothers smoked during pregnancy may be at higher risk for Sudden Infant Death Syndrome (SIDS) than preemies whose mothers did not smoke. This is the first study to investigate the effect of low oxygen and cigarette smoke exposure on infants' heart rate and breathing responses.
“Smoking during pregnancy has two very serious effects with respect to SIDS,” says Dr. Shabih Hasan, a neonatologist and Professor in the Department of Pediatrics at the Faculty of Medicine, University of Calgary. “Not only does it raise the likelihood of a mother having a preterm baby, who are already among the most vulnerable to SIDS, but it increases those infants’ susceptibility to SIDS even further.”
Sarah Spensley took part in this ground breaking study after her daughter Leah was born eight weeks premature. The non-smoking mother says the research results are important or families.
“Anything that shows evidence about what smoking can do to your baby, any information that encourages women to stop smoking before they are pregnant, is a good thing.”
While preterm babies are known to have increased breathing difficulties in proportion to their prematurity, and cigarette smoke is known to increase apneas in full-term babies, cigarette smoke exposure and low oxygen in blood had never been investigated as complicating factors in relation to pre-term babies and respiratory dysfunction.
“We wanted to investigate the effects of prenatal cigarette smoke exposure on the duration and recovery of breathing pauses under normal and low-oxygen situations,” says Hasan, the principal investigator of the new study.
The study is the cover story of the September 1 issue of the American Journal of Respiratory and Critical Care Medicine, a leading international respiratory journal. The study was conducted at the Neonatal Intensive Care Unit (NICU) at the Foothills Medical Centre in Calgary.
To investigate the possibility of cigarette smoke exposure as a complicating factor in preterm infants’ respiratory health, and its potential influence on their risk of SIDS, researchers recruited 22 preterm infants who had been spontaneously born between 28 and 32 weeks, with no other complicating respiratory factors. Twelve of the infants had mothers who had smoked five or more cigarettes every day in pregnancy. The mothers of the other ten infants did not smoke during pregnancy.
Hasan’s research is supported by the Canadian Institutes of Health Research (CIHR), the Alberta Heritage Foundation for Medical Research (AHFMR), and the Calgary SIDS Society. He is a member of the Institute of Maternal and Child Health.
The cover of the American Journal of Respiratory and Critical Care Medicine can be viewed at: http://ajrccm.atsjournals.org/content/vol178/issue5/cover.shtml . Please feel free to use images of the cover.
