The mother is an important mediator to the infant of polyunsaturated fatty acids (PUFA), the essential constituents of membranes particularly in the brain and retina. We here aimed in a prospective study initiated in early pregnancy to establish whether serum fatty acid (FA) compositions and concentrations in the mother can be modified by dietary means emphasizing counseling on a recommended diet.

Ninety women in the first trimester of pregnancy were randomized into intervention (n=45) or control (n=45) groups. The intervention comprised individual dietary counseling advocating choice of foods that will increase the intake of unsaturated and reduce that of saturated FA. To support this, appropriate products, including spreads, were provided for consumption at home. Dietary intakes were measured from food records and serum phospholipids, cholesteryl esters and triacylglycerols FA were analyzed by gas chromatography.

Dietary counseling resulted in lower intake of saturated and higher intake of unsaturated FA compared with the controls. These changes were reflected in higher proportions of serum phospholipid PUFA (mean difference between groups 0.61% (95% confidence interval, CI 0.05-1.17), P=0.03), docosahexaenoic acid (0.5% (0.15-0.85), P=0.01), sum of n-3 FA (0.61% (0.07-1.15), P=0.03) and lower ratio of n-6/n-3 FA (-0.42% (-0.81-0.03), P=0.03) in the intervention group at the third trimester of pregnancy but not at 1 month postpartum. Similar changes were seen in the FA of cholesteryl esters and triacylglycerols.

Maternal serum n-3 FA status during pregnancy can be improved by dietary means emphasizing the importance of dietary advice.