Longitudinal study of fatty acids in plasma and erythrocyte phospholipids during pregnancy.

Aim: To assess the modifications of the main fatty acids (FA) in plasma and red blood cells during pregnancy.
Methods: A longitudinal study of 36 normal pregnant women was carried out with 3 cut-off points: first trimester, second trimester and third trimester. 14 FA in plasma and erythrocyte phospholipids were measured using capillary gas chromatography. Measurements were expressed in percentages and in absolute values.
Results: In plasma there was a significant increase in the proportion of saturated FA and a decrease in the proportion of long chain polyunsaturated fatty acids (PUFA) both in the omega 6 (omega 6) and omega 3 (omega 3) series. On the other hand, in erythrocyte phospholipids there was a decrease in the proportion of eicosapentaenoic acid and an increase in that of docosahexaenoic acid. In the omega 6 series, dihomo-gamma-linolenic acid increased, whereas the omega 6 docosapentaenoic acid decreased.
Conclusion: There was a significant decrease in the proportion of omega 3 PUFA in plasma from the first to the third trimester. Thus, it is suggested that the omega 3 PUFA intake during pregnancy should be increased in the last trimester.