Results
Demographic characteristics of participants are shown in Table 1, which highlights that most participants were aged
25–34 years, were in their second or third trimester of preg-nancy and were well educated. Family income was similar to 2011 census data for the Illawarra statistical local area,31 which reported a median weekly family income for residents aged 15 years and over of $1413 (annual $73 476) compared with $1477 (annual $76 804) for New South Wales and $1481 for Australia (annual $76 960) . Fifty-five per cent of women had a university degree compared with 45% of high school and TAFE or apprenticeship degree, which is higher than the national average for Australia (23.2%).32 Most women (81.6%) indicated that they used supplements during their pregnancy, and many (63.4%) indicated that they had started consuming supplements during the current pregnancy, rather than preconceptually (Figure 1). Two-thirds (67.7%) of women reported that they took supplement brands that contained both folic acid and
iodine. Only 4.6% were taking supplements containing only folic acid, and a further 9.2% consumed other nutritional
supplements, containing vitamin D, fish oil, vitamin C, calcium and iron (see Table 2). Fifty-six per cent of women
reported that they took supplements once daily, with an estimated monthly cost ranging from $7.47 to $16.78. Supplement use was significantly higher among women who were in the highest household income category as compared with those in the lowest category (69.2 vs 30.8%; P = 0.001). Open-ended responses from participants who were not taking supplements (n = 28, 18.4%) suggested that they had not been advised to do so by their doctor (26.7%), they could not tolerate them because of nausea from morning sickness (20%), they could not afford to purchase the supplements (20%), they did not feel that they needed