Sociodemographic Variation in Prenatal Aneuploidy Screening and First‐Line Non‐Invasive Prenatal Testing: A Multicentre Cohort Study

Objective To examine prenatal aneuploidy screening uptake and modality in a high‐income setting where non‐invasive prenatal testing (NIPT) is recommended but remains self‐funded, and to investigate variation by sociodemographic and clinical characteristics. Method We conducted a retrospective multi‐centre study of women who gave birth at ≥ 20 weeks' gestation across 11 public hospitals in Melbourne, Australia from 2022–2024. Maternity and pregnancy covariates were collected from routine maternity hospital databases. Result Of 102,729 women, screening data were available for 80,355 (78.2%); 66,343 (82.6%) had aneuploidy screening, 12,632 (15.7%) declined, and 1380 (1.7%) were not offered screening. Women who declined screening were more likely to be younger (< 30 years), multiparous, or migrants from specific regions. Among screened women, NIPT was the predominant modality (80.6%, n = 53,475), followed by combined first trimester screening (16.6%, n = 10,991) and second trimester serum screening (2.5%, n = 1634). NIPT uptake increased from 75.3% in the most disadvantaged regions to 88.9% in the most advantaged regions and remained associated with socioeconomic advantage after adjustment (aIRR 1.09, 95% CI 1.06–1.13 for most advantaged vs. most disadvantaged regions). Conclusion NIPT was the predominant screening modality; however, its uptake was strongly associated with socioeconomic advantage, suggesting variation in uptake of the most accurate aneuploidy screening test in Australia.