Sociodemographic factors associated with sleeping position and location.

Recent research has implicated infant sleeping body position and bed sharing as risk factors in the sudden infant death syndrome. The sociodemographic associations of infant sleeping body position and location were examined in this study. This showed that the majority (86.4%) of New Zealand parents now place their infants to sleep on their sides. The remainder place their infants supine (1.3%), prone (4.8%), or no particular way (7.5%). In the waking position, 57.9% were usually found on their sides, 18.2% supine, and 6.1% prone. Infant sleeping position showed marked sociodemographic variability. These findings are a marked contrast to previous New Zealand studies which showed a reversed pattern, with most infants put to sleep prone. There were also highly significant sociodemographic differences in the place of sleeping. Overall 12.2% of infants shared a bed, with infants of younger less well educated mothers who were of non-European origin, with a parity of five or more, or unmarried significantly more likely to do so. Infants of unemployed and lower socioeconomic group (Elley-Irving groups 5 and 6) fathers were also more likely to share a parental bed.