Association between prenatal and current exposure to selected LCPUFAs and school performance at age 7

Long-chain polyunsaturated fatty acids (LCPUFAs) are important for brain functioning and might, thus, influence cognition and school performance. However, research investigating LCPUFAs relationships with school performance is limited. The objective of this study was to determine the association between levels of the LCPUFAs docosahexaenoic acid (DHA), arachidonic acid (AA), eicosapentaenoic acid (EPA) and n-6 docosapentaenoic acid (Osbond acid, ObA) at study entry, 22 weeks of pregnancy, 32 weeks of pregnancy, at partus, in umbilical cord plasma and child's plasma at age 7 and school performance scores at age 7.

Data from the Maastricht Essential Fatty Acid Birth cohort (MEFAB) were used for this study. Fatty acid levels of plasma phospholipids were measured in maternal blood plasma at study entry, 22 weeks of pregnancy, 32 weeks of pregnancy and partus. Childs fatty acid levels of plasma phospholipids were measured a in umbilical cord blood plasma, and in blood plasma of the child at age 7. Scores on national standardised tests for spelling, reading and arithmetic at age 7 were obtained via the school (scores were available for 149, 159 and 155 children, respectively). Associations between LCPUFA levels and school performance scores were analysed with categorical regression analyses with correction for covariates (smoking, maternal education, sex, breastfeeding, maternal intelligence, birth weight and BMI at age 7).

Significant (p<0.001) associations between DHA level at age 7 and both reading (β=0.158) and spelling (β=0.146) were found. Consistent significant negative associations were observed between all maternal DHA plasma levels and arithmetic scores at age 7 (all p<0.001, all β<-0.019). Additional significant negative associations were observed between maternal LCPUFA plasma levels at study entry and both reading and spelling scores at age 7; these associations were less consistent.

Plasma DHA levels at age 7 were positively associated with reading and spelling scores at age 7. Consistent significant negative associations between maternal plasma DHA levels and arithmetic scores of the child at age 7 were found. Although this is an observational study, which cannot proof causality, the consistent negative associations observed between maternal plasma DHA levels and the arithmetic scores of the children at age 7 calls upon prudence when considering DHA supplementation during pregnancy.