Perinatal Outcome in Western Australia, 1968 to 1975.; 2. Social and Biological Determinants

Trends in perinatal mortality and low birth-weight (percentage of livebirths under 2500 g) were analysed in relation to certain social and biological variables. Mothers at high risk of adverse perinatal outcome in terms of perinatal mortality and low birthweight were found to be very young and grand multiparous mothers, old primiparas, unmarried mothers, those with multiple pregnancies and mothers born in Asia. The marked changes in the maternal age and parity distributions of all births had little effect on adverse perinatal outcomes. European migrant mothers initially (1968 to 1971) were at high risk, but have shown more rapid improvement in outcome than any other group and were more recently (1972 to 1975) at lowest risk.