Ethnicity and birth outcome: New Zealand trends 1980-2001: Part 3. Pregnancy outcomes for Pacific women

BACKGROUND: Pacific women in New Zealand reside in areas of higher socioeconomic deprivation compared to women from other ethnic groups. Pacific women and their health are further disadvantaged because of genetic predisposition and sociocultural factors that cause ill-health. The correlations between pregnancy outcomes, risk factors and other health indices in Pacific women need evaluation. AIMS: To examine trends in preterm birth, small for gestational age (SGA) and late fetal death for Pacific women during 1980-2001 and to explore risk factors which make this group vulnerable to adverse birth outcome. METHODS: De-identified birth registration data from 1 189 120 singleton live births and 5775 stillbirths were analysed for 1980-2001. Outcomes of interest included preterm birth, SGA and late fetal death while explanatory variables included maternal ethnicity, age and NZ Deprivation Index decile. Trend analysis was undertaken for 1980-1994 and multivariate logistic regression was used to explore risk factors for 1996-2001. RESULTS: Pacific women had the lowest rates of preterm birth and SGA when compared to Maori and European women. In addition, preterm birth rates underwent a non-significant 4% decline and SGA rates a 30% decline during 1980-1994. Although there has been a 49% decline in late fetal deaths during 1980-1994, the rate remained higher for Pacific women than for Maori and European/other women. CONCLUSIONS: Despite residing in areas of high socioeconomic deprivation, which is associated with poor pregnancy outcomes for Maori and European/other women, Pacific women had better pregnancy outcomes, with lower preterm and SGA rates. The significant decline in rates of late fetal death during the past two decades is a cause for celebration; however, the rate remains higher for Pacific women than for other ethnic groups. Biological, cultural and social factors might explain the better pregnancy outcomes for Pacific women and these factors should be considered when developing future prevention programmes.