the risk was greatest in babies sleeping .
a new meta - analysis compared four previous studies and found that of all the infants who died of sids , 17 percent had been swaddled .
although the benefits and risks of swaddling in general have been studied , the practice in relation to sudden infant death syndrome remains unclear .
data sources : additional data on sleeping position and age were provided by authors of included studies met the inclusion criteria .
study selection : observational studies was 1.58 ( 95 % confidence interval [ ci ] , 0.97–2.58 ) .
objective : the goal of this study was to conduct an individual - level meta - analysis of sudden infant death syndrome risk for infants swaddled for sleep .
researchers pooled data from four observational studies of sids and swaddling that included 760 sids cases and 1,759 controls .
over all , swaddling increased the risk for sids by about one - third .
results : there was significant heterogeneity among studies of the subject , and the amount of good evidence is limited .