Introduction:
Prenatal alcohol exposure (PAE) is a known contributor to intrauterine growth restriction, adverse organ development, and neurodevelopmental delay. Accurate identification of alcohol-exposed pregnancies is important for effective antenatal supports. Despite known effects of PAE on birth outcomes and later life health, there is little consensus on its true prevalence in Australia.
Objectives:
To examine prenatal alcohol exposure (PAE) data collection approaches in Australian pregnancy and infant cohort studies and evaluate their impact on reported prevalence and patterns of PAE.
Study design:
Systematic review of peer-reviewed published articles describing prevalence and patterns of PAE in Australia.
Data sources:
PubMed, Embase, CINAHL, Web of Science, Informit, and Scopus, including peer-reviewed articles published from database inception until June 2020.
Data synthesis:
Data was extracted from 110 manuscripts, including 15 large (>1,000 participants) and 46 small (<1,000 participants) and/or case-control studies. Two large cohort studies were primarily focused on PAE, which included detailed questionnaires on amount and frequency of alcohol consumption in each trimester of pregnancy and estimated overall prevalence of PAE as sixty to seventy percent. In the other studies, questions regarding alcohol use in pregnancy were often asked post-pregnancy or once during pregnancy by questionnaire or interview. In these, prevalence of PAE was forty to sixty percent. Self-administered questionnaire-based methods that included questions on amount consumed and frequency, reported prevalence estimates closer to the alcohol-focussed cohort studies. Across all cohorts, reported level of alcohol exposure was typically low (1-2 standard drinks) and infrequent (once per week or less).
Conclusions:
The two alcohol-focussed studies reported higher prevalence of PAE and provided detailed information on timing and amount of alcohol consumed. Estimates from other studies were most similar when self-administered questionnaires and information on dose and frequency were included, suggesting these should be adopted in future pregnancy and/or infant studies to provide reliable PAE estimates.