Prevalence of prenatal alcohol use among Aboriginal and non-Aboriginal women in the Northern Territory, Australia: estimate from perinatal, emergency, and admission datasets.

BACKGROUND: Prenatal Alcohol Use (PAU) has detrimental effects on mothers and their children. Robust estimates of the prevalence of PAU and associated risk factors are critical for informing interventions to reduce adverse health impacts. This study aimed to estimate the prevalence and risk factors of PAU among Aboriginal and non-Aboriginal mothers in the Northern Territory of Australia. METHODS: We used linked individual-level records from the NT perinatal register, hospital admissions, and emergency department presentations to estimate the prevalence of PAU for all 19,588 births to NT-resident women from 2013 to 2017. Permutation analysis was used to create four PAU categories: no PAU, early PAU (alcohol use in early pregnancy only), continued PAU (alcohol use in early and late pregnancy), and extreme PAU (hospital admissions/ presentations for alcohol-related diagnosis during pregnancy). Multinomial logit models explored the associations between sociodemographic and clinical factors and degrees of PAU. A relative risk ratio (RRR) with a 95% confidence interval (CI) was used to measure associations. RESULTS: There were 19,588 births to 16,199 women during the study period (6,310 births to 5,207 Aboriginal women). The mean gestational age at birth for Aboriginal women was 37.8 (95% CI: 37.7, 37.9) weeks and 38.7 (38.6, 38.8) weeks for non-Aboriginal women. The overall PAU prevalence for births to Aboriginal women was 13.1% (95% CI: 12.2, 14.0), including 5.9% (95% CI: 5.2, 6.5) early PAU, 4.3% (95% CI: 3.8, 4.8) continued PAU, and 2.8% (95% CI: 2.4, 3.3) "extreme" PAU. The overall prevalence for non-Aboriginal women was 2.3% (95% CI: 2.1, 2.6), including 1.7% (95% CI: 1.5, 1.9), 0.53% (95% CI: 0.4, 0.7) and 0.1% (95% CI: 0.02, 0.1) for each category, respectively. Age, smoking, and substance misuse-related hospitalisation were associated with an increased risk of PAU among both populations. Being a victim of violence was an additional risk among Aboriginal women. More than five antenatal care (ANC) visits were associated with less PAU. However, 17.9% (n = 3520) of births had missing records related to PAU. CONCLUSION: The study provides refined prevalence estimates for PAU across groups with increasing risk of harm. Early identification and effective engagement with women at risk of PAU are critical for improving outcomes for mothers and their children. Targeted interventions like enhanced services that support cessation of alcohol and other drugs (AOD), strengthening families, and sustained engagement with culturally safe, trauma-informed maternity care may aid in reducing PAU. The study also highlights the critical need to enhance both the quality and completeness of the routine recording of alcohol use during pregnancy.