Is baby too warm? The use of infant clothing, bedding and home heating in Victoria, Australia.

Overheating of infants has been associated with a raised risk for sudden infant death syndrome (SIDS). Data on the use of heating, bedding and clothing and other measures affecting the thermal environment of 4 week old infants were collected at a home interview for infants of women born in Australia (Anglo-Celtic background), in Southern Europe, in Asia and of women who had a planned out-of-hospital birth. These groups have different risks of SIDS not explained by the classic social and perinatal risk factors nor associated with the currently promoted 'new' risk factors. Thermal insulation of the infant's bedding and clothing and excess thermal insulation (for any observed room temperature) were calculated. Bed sharing differed significantly between the groups as did the use of a sheepskin, tucking in firmly, the closing of doors and windows and the use of heating in the infant's room. After stratifying by bed sharing practice and season of interview, it was found that bed sharing infants had more thermal insulation than those sleeping alone irrespective of season of interview. Infants sleeping alone in the Asian-born and Southern European-born groups were kept warmer than infants in the other two groups. Cultural factors appear to affect the thermal environment in which infants are raised. Some bed sharing infants in all four groups were inappropriately warm, particularly in colder weather, but this was more likely in the Asian-born (low risk) group than in the home birth (high risk) group. These results do not explain the differences in SIDS incidence between the groups.