Omega-3 fatty acids to prevent preterm birth: Australian pregnant women’s preterm birth awareness and intentions to increase omega-3 fatty acid intake

A cross-sectional research design was performed among Australian pregnant women (or those who had given birth within the previous six months). A 43-item survey was developed based on best practice principles [9] and evaluated by health professionals and women who had given birth to assess the knowledge, attitudes, behaviours, and intentions of pregnant women (survey items listed in the Additional file 1). The survey was subsequently pilot tested by 100 participants for feasibility. Two screening questions were first included to exclude women who indicated they were not pregnant or had not recently given birth, or who did not agree to participate after reading the participant information sheet. In addition to demographic data (15 items), information was collected across three domains: (1) preterm birth; (2) nutrition and supplementation during pregnancy; and (3) omega-3 fatty acid consumption to prevent preterm birth. In the final stage of the survey, respondents were asked about behavioural intentions to change their omega-3 fatty acid intake following presentation of information on preterm birth and its consequences, an omega-3 fatty acid evidence statement and recommendation. Throughout the survey, omega-3 fatty acids were referred to as omega-3 s. Responses to the key survey items are detailed in the results section.

Ethical approval for this study was granted by the Women’s and Children’s Health Network Human Research Ethics Committee in Adelaide, Australia (HREC/17/WCHN/155). An information sheet outlining the purpose of the survey was provided with the link to the survey. Completing the online survey implied consent.

Respondents were recruited through Survey Sampling International’s (now Dynata) research panels and responses to the online survey were collected between August 2018 and January 2019. Women were eligible for the survey if they were currently pregnant or had given birth within the last six months, were over the age of 18 years, living in Australia, and willing to participate in the study. Women were excluded if they indicated at the screening question that they were currently pregnant but answered “0” when asked their gestational age.

Data coding and analyses were performed using SPSS (SPSS, version 25.0, Armonk, NY, USA). Descriptive statistics were reported as frequencies and percentages; or medians and lower and upper quartiles. The distributions of continuous variables were assessed for normality using the Shapiro-Wilk test. As data were not normally distributed, non-parametric tests were conducted when testing for differences between groups; the Mann Whitney U test was used for continuous variables and Fisher’s exact test (chi-square) was used for categorical variables. All analyses were two-sided and statistical significance was set at a P-value less than 0.05. Subgroup analyses were performed on relevant questions to investigate differences in responses between nulliparous and multiparous women.

Seven hundred and sixty three women (n = 763) completed the survey. Demographic characteristics are displayed in Table 1. The median (interquartile range) age and body mass index (BMI) of respondents was 30 years (26–34) and 24.1 kg/m² (20.8–29.0), respectively. Overall, 87.9% of respondents indicated that they had completed high school; 84.8% of those completing high school had completed further education. Women expecting their first baby were significantly younger than those who had previously given birth, and were more likely to have completed high school.

Although the respondents in this study had similar demographic characteristics to Australian women delivering in 2016 [10], the women included in this study were more likely to be born in Australia, identify as Aboriginal and/or Torres Strait Islander, and were more likely to indicate they had smoked during pregnancy.

Only 61.6% of respondents had heard of preterm birth, whereas 84.0% had heard of premature birth. Multiparous women were significantly more likely to have heard of preterm birth than nulliparous women (65.7% vs 55.5%; P = 0.02). Overall, 52.7% indicated they were most familiar with the term “premature birth” out of the four synonyms presented (“preterm birth”, “premature birth”, “premmie baby”, and “prem baby”). Only 37.9% of the respondents correctly defined premature birth as “birth before 37 weeks of gestation”, when provided with eight response options (ranging from “birth before 32 weeks” to “birth before 42 weeks”, and the option of “a baby born with a low birthweight”). Multiparous women were significantly more likely to correctly answer the definition of premature birth than nulliparous women (43.0% vs 30.5%; P = 0.02).

Of the women who had heard of preterm birth (or its synonyms) before commencing the survey, the main source of information about preterm birth was through a health professional (n = 290; 55.8%). The next most common source was the internet (n = 179; 34.4%), followed by family (n = 153; 29.4%) and friends (n = 135; 26.0%).

A dietary supplement was consumed during their current pregnancy by 625 (81.9%) of the women surveyed and nulliparous women were more likely to be consuming a dietary supplement than multiparous (87.0% vs 78.4%; P = 0.01). The nutrient supplement most commonly consumed by respondents was a pregnancy multivitamin (73.4%), followed by folic acid (48.3%). The main motivation for deciding to consume a nutrient supplement during pregnancy was “for the health of the baby” (71.7%), closely followed by the influence of an external recommendation (68.8%), and “for maternal health and well-being” during pregnancy (60.0%) (Table 2).

Respondents sought information on nutrition during pregnancy from a range of sources: the most common sources of information were health professionals (82.3%) and information from friends and family members (45.3%). When asked about who has the greatest influence on their decision to take or not take nutrient supplements during pregnancy, respondents nominated health professionals, and friends and family members (76.8 and 32.4%, respectively). Although pregnancy blogs and the general internet were selected by respondents as sources of nutrition information, they were much less likely to indicate these sources as key influencers in their decision to take supplements in pregnancy (Fig. 1).

A high proportion of respondents (90.6%) had heard of omega-3. Omega-3 fatty acid containing supplements had been consumed by 37.7% of respondents in the 12 months prior to conceiving and 30.4% indicated that they had consumed an omega-3 fatty acid containing supplement during their current pregnancy. Less than a third of the women surveyed (32.1%) were eating at least two serves of fish a week and 19.3% indicated they never ate lean or fatty fish during their pregnancy.

When asked about their intentions to increase their omega-3 fatty acid intake following a government guideline and health professional’s recommendation, a high proportion indicated they would increase their omega-3 fatty acid intake (89.5%), with 53.7% preferring to take an omega-3 fatty acid supplement and 35.8% preferring to increase their omega-3 fatty acid intake from food sources (Table 3). Of the 10.5% (n = 80) who indicated they would not make any changes to their omega-3 intake, about a third felt they already had a good diet/were getting enough omega-3 fatty acids (n = 26; 32.5%,). However, only two (7.7%) of the respondents who felt they were already getting enough omega-3 fatty acids ate two or more serves of fatty fish per week.

Although roughly half (53.7%) of respondents indicated they would increase their omega-3 fatty acids by taking an omega-3 fatty acid supplement during pregnancy, if an omega-3 fatty acid supplement were offered at no cost from a health service, 78.8% of respondents indicated they were likely or highly likely to do so (Table 4).