Sudden infant death syndrome in South Australia 1968-97. Part I: Changes over time

Objective: To compare the epidemiology of sudden infant death syndrome (SIDS) over three consecutive decades. Methodology: The birth history, infant's developmental and health history, infant care practices for the infant, death scene investigation and autopsy findings for all infants dying suddenly and unexpectedly in South Australia (SA) between January 1968 and December 1997 were studied. Results: The incidence of SIDS in SA rose through the 1970s and early 1980s with the highest incidence being in infants born in 1986 at 2.4 per 1000 Live births (LB). Two factors felt to be dangerous for some infants were identified - being left unobserved in the prone position and having the head covered by bed clothes. Publicity about the risk of prone sleeping has been accompanied by a fall in SIDS deaths, to an incidence of 0.5 per 1000 LB in 1997. The incidence in Aboriginal infants, and infants living in lower socio-economic conditions has always been high but the over-representation of these groups has increased in the last 5 years. Conclusion: If no infant under 8 months of age was placed prone or was able to get to prone unobserved before the age when they can easily get back to supine, and no infant was able to get the head completely covered while unobserved, the incidence of SIDS in SA should fall below 0.2 per 1000 LB.