TRENDS IN PERINATAL CHARACTERISTICS IN SOUTH AUSTRALIA, 1981 TO 1994,BY PLACE OF RESIDENCE OF MOTHER

We investigated differentials and time trends in perinatal mortality a nd perinatal risk factors by geographic area of residence in South Aus tralia during 1981-1994, to assess whether sociodemographic inequaliti es had lessened. The areas analysed were Adelaide and the country regi on of South Australia, with Adelaide being divided by socioeconomic st atus into two areas. Subjects were 267 116 singleton births of at leas t 400 g birthweight (or at least 20 weeks' gestation) notified to the state's perinatal data collection. Year of birth, residential area, an d interactions between year of birth and residential area were analyse d as predictors of perinatal risk factors and deaths. There was a stat istically significant decline in the perinatal death rate in all resid ential areas (mainly because of a decrease in neonatal deaths), which did not vary significantly by area. The frequency of low birthweight ( <2500 g) increased in the country areas and in the lower socioeconomic areas of Adelaide, but not in the higher socioeconomic areas. Althoug h premature births increased in all areas, the increase was less prono unced for the higher socioeconomic areas of Adelaide. By comparison, a lthough all areas showed an increase in the proportions of mothers age d 35 years or over, the increase was larger for the higher socioeconom ic areas. Australia has a national policy of reducing social inequalit ies in health status. Perinatal mortality rates declined in Adelaide a nd country residential areas from 1981 to 1994. This trend is favourab le, but from the relativities of these rates by residential area, ther e is not compelling evidence of a reduction in inequalities.