A wide range of maternal demographic variables was collected. [19] The variables and the classifications used in this paper are maternal age (<30, 30–34, ≥35 years), parity (0, ≥1), marital status (partnered/un-partnered), ethnicity (Caucasian (e.g. White Australian, UK, other European), Asian and other (e.g. mixed race), education (secondary, diploma/trade, university degree), gross household income per year (up to $40,000, $40–100,000, >$100,000 AUD), current financial situation (living comfortably, doing all right, just getting by, struggling), region of residence (metropolitan, rural), smoking (no, yes) and planned pregnancy (no, yes). Maternal report of height and pre-pregnancy weight were used to calculate body mass index (BMI). To gauge possible individual variation in alcohol metabolism, the women were asked if they felt the effects of alcohol very quickly, quickly, normally, slowly, or very slowly. Women were also asked about their drinking history, how old they were when they first started drinking regularly, if they had ever been intoxicated after drinking alcohol (defined as slurred speech, unsteady on their feet, or blurred vision) and the age when they first became intoxicated from drinking alcohol. Responses were categorised by age into <18 years and ≥18 years to reflect the legal drinking age in Australia.
