A study explored the breathing reflexes of preterm babies of smokers and compared them with those of non smokers.
Researchers found that the babies whose mothers had smoked showed signs of impaired respiratory function.
Findings were based on a study of 22 preterm infants born between 28 and 32 weeks with no other complicating respiratory factors.
In the sample group, 12 of the infants had mothers who had smoked five or more cigarettes every day in pregnancy. The mothers of the remaining 10 did not smoke during pregnancy.
Baseline readings were obtained for infants’ breathing patterns in normal conditions, assessing breathing rate, pauses in breathing, recovery period, blood oxygen saturation and heart rate.
Infants were challenges with a five-minute period of decreased oxygen delivered through a nasal cannula, while the infant was monitored with resuscitation equipment at hand.
Cigarette smoke exposed infants showed increased heart rate during the hypoxemic period compared with baseline values and blood oxygen levels recovered more slowly.
Report author Shabih Hasan, of the University of Calgary, said: ‘Our study shows that preterm infants make incomplete and/or delayed recovery from interruptions in breathing. This has clear implications for their risk of SIDS.’
American Journal of Respiratory and Critical Care Medicine (2008) 178: 520-526