Infants who sleep with their parents are seven times more likely to die of Sudden Infant Death Syndrome than children who sleep on their own, according to a new study. Dick Ahlstrom, Science Editor, reports.
Co-sleeping with mothers who smoked during pregnancy is also a significant risk factor for infants under 20 weeks, the five-year study of more than 800 Irish babies concludes.
The study, led by Dr Cliona McGarvey of the National Sudden Infant Death Register and published today in the British Medical Association's journal, Archives of Disease in Childhood, highlights a range of factors that together increase the risk of Sudden Infant Death Syndrome (SIDS) 16-fold.
The absence of routine soother use prior to the infant's death was also a significant risk factor, according to the study, which found that more SIDS cases than controls habitually used soothers in this study.
"However, 47 per cent of these babies did not have their soother on the night they died." They were six times more at risk of SIDS without their soother than regular users who did have it.
The study found that particular dangers included co-sleeping with parents, maternal smoking and infants sleeping in the prone (lying face down) position.
SIDS remains the leading cause of infant death in developed countries and accounts for four of every 10 infant deaths here, according to the authors. They note that the SIDS rate had dropped steeply here after information campaigns warning parents to avoid placing children to sleep in the prone position, from two per 1,000 live births to 0.8 per 1,000 live births.
The study included 203 SIDS cases and 622 control infants born between 1994-98.
It found that "co-sleeping increases the SIDS risk by a factor of seven. This figure was increased to 16.47 when adjusted" for other factors, the authors report.
Age was a key consideration, with the risk associated with bed sharing not significant for infants older than 20 weeks.
The study found that 39 per cent of SIDS cases were co-sleeping and had mothers who smoked during pregnancy, compared with only one per cent of controls. Some countries, including Norway, recommended co-sleeping as a way to increase breast feeding, "which in itself has been said to reduce the SIDS risk," the authors note.
"Our data show that bed-sharing does not pose a risk if the infant is placed back in their own cot to sleep, as only infants who were bed-sharing for the entire sleep period were at increased risk of SIDS."