Risk factors for stillbirth in a socio-economically disadvantaged urban Australian population

Introduction: Several risk factors for stillbirth have been extensively investigated. Some risk factors are more common in socio-economically disadvantaged regions. The aim of this study was to identify risk factors for stillbirth in the Northern suburbs of Adelaide, one of the most socio-economically disadvantaged urban areas in Australia. Material and methods: A retrospective case control study (two controls per case) of all women with a singleton pregnancy resulting in a stillbirth during the decade 2002–2012. Results: One hundred and thirty stillbirths were registered over these 10 years. Using univariate analysis, the following risk factors were identified: obesity ≥40 body mass index (BMI) (OR 4.75), non-Caucasian ethnicity (odds ratio [OR] 2.737), pre-existing diabetes (p <0.000), polycystic ovary syndrome (PCOS) (OR 5.250), in vitro fertilisation (IVF) (OR 4.000), booking systolic blood pressure (SBP) ≥ 140 (OR 5.000) and booking diastolic blood pressure (DBP) ≥ 80 (OR 3.111). Many of these factors have complex interrelationships. Multivariate analysis identified the following independent risk factors: BMI ≥40 (OR 3.940), ethnic minorities (mainly indigenous Australians) (OR 2.255) and social issues (OR 3.079). PCOS had an independent effect to some extent, but this was clearly confounded by BMI. Conclusion: These Australian data confirm the presence of several potentially modifiable risk factors for stillbirth, within this socio-economically disadvantaged region. Modifying these risk factors, in particular obesity, is a big challenge not only for maternity and primary care providers, but for overall society.