Spearman’s correlation coefficients (<i>r_s</i>) between background variables/other potential risk factors for PPD^† measured in pregnancy, and the omega-3 index^‡ in pregnancy, and EPDS^§ score postpartum (n = 35).

*<p>Significant at <i>p</i><0.01.</p>†<p>Postpartum depression.</p>‡<p>The content of EPA+DHA in red blood cell membranes expressed as a percent of total fatty acids.</p>§<p>Edinburgh postpartum depression scale.</p>∥<p>n = 33 (two participants with no partner).</p

Fatty acid profile of the study population, and Pearson’s correlation coefficients between the fatty acids in red blood cells, expressed as relative amount, and the EPDS^‡ score (n = 43).

†<p>Measured fatty acid value below the limit of quantification for the method.</p>‡<p>Edinburgh postpartum depression scale.</p>§<p>Correlation between % of total fatty acid and EPDS.</p>∥<p>The content of EPA+DHA in red blood cells membranes expressed as a percent of total fatty acid.</p>¶<p>Total HUFA is the sum of the omega-3 and the omega-6 HUFAs, and the red blood cells omega-3 HUFA score equals 100% - omega-6 HUFA.</p

Socio-economical and behavioural characteristics of study participants (n = 55).

†<p>University or university college.</p>‡<p>n = 53 (2 participants with missing data).</p>§<p>100 000 NOK ≈ 14 000 EUR.</p>∥<p>n = 54 (1 participant missing data).</p

Flow chart of the study design.

<p>* Of which one respondent did not provide a blood sample ** Of which 54 responders and 15 non-responders to the electronic questionnaire *** Of which 35 responders and 8 non-responders to the electronic questionnaire. 26 participants were not screened for depression 3 months postpartum due to drop out or losses to follow up.</p

Participant’s response to the electronic questionnaire in pregnancy.

<p>Bar chart presenting the median EPDS score measured 3 months postpartum of non-responders (n = 8) and responders (n = 36) to an electronic questionnaire (seafood intake, demography, socioeconomically status, psychological status) in pregnancy. * Significantly difference at the 0.001 level. † 28th week gestation. ‡ Edinburgh postnatal depression scale.</p

Association between the omega-3 index in pregnancy and postpartum depression.

<p>Scatter plot of the non-linear relationship between the marine omega-3 status (omega-3 index) in pregnancy and postpartum depression score (EPDS). A rectangular hyperbolic equation (<i>y</i> = -1.31+28.1/x) was the best fit for describing this relationship (<i>ß</i> = 0.43, <i>F</i> (1,41) = 9.32, <i>p</i><0.004, n = 43). The vertical lines represent omega-3 index quartiles. Red markers represent individuals in the 25 percentile. † The content of EPA+DHA in red blood cells membranes expressed as a percent of total fatty acids ‡ Edinburgh postnatal depression scale.</p

Association between the omega-3 index and absolute DHA and EPA in red blood cells.

<p>Scatter plot of the omega-3 index and the corresponding DHA content (µg/g) and EPA content (µg/g) in red blood cells, and the respective fitted regression lines. The omega-3 index is the content of EPA+DHA in red blood cells membranes expressed as a percent of total fatty acids.</p

Seafood consumption and prevalence rates of postpartum depression.

<p>Postpartum prevalence rates for Australia, New Zealand, Sweden and the United Kingdom, The United States were derived by meta-analysis. All other countries are represented by a single study, see text. Apparent Seafood consumption lb/person/year is an economic measure of disappearance of all fish and seafood from the economy and is calculated by imports plus catch minus exports. A logarithmic regression was used for analysis (<i>r</i> = −0.81, <i>p</i><0.001). In Norway the seafood consumption is (47 lbs/person/year = 21,3 kg/person/year <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067617#pone.0067617-Helsedirektoratet1" target="_blank">[94]</a> and the prevalence of postpartum depression is 10% <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067617#pone.0067617-Berle1" target="_blank">[3]</a>. Modified from Hibbeln <i>et al. </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067617#pone.0067617-Hibbeln2" target="_blank">[30]</a>.</p

Additional file 1: Table S1. of Fatty fish intake and attention performance in 14–15 year old adolescents: FINS-TEENS - a randomized controlled trial

Changes within and between treatments in reported meals per week (besides the intervention) of background diet from pre to post. Data given as mean ± SD or mean (95% CI). n = 137 in fish group, n = 148 in meat group and n = 141 in supplement group. (DOCX 18 kb

Descriptive, socio-economic and behavioral characteristics of study participants (T1 n = 55, T2 n = 92, T3 = 82 and T4 = 78).

<p>* An independent sample t-test was applied to normal data (age) and Man-Whitney for non-normal data (BMI, education, employment, marital status, own income and breastfeeding)</p><p>¹ Age and BMI are presented as mean ± SD</p><p>² BMI pre-pregnancy</p><p>³ University or University College</p><p>⁴ Data not requested at time point 3 and 4 (no new recruitment)</p><p>⁵ 100 000 NOK ≈ 14 000 EUR</p><p>Descriptive, socio-economic and behavioral characteristics of study participants (T1 n = 55, T2 n = 92, T3 = 82 and T4 = 78).</p