Cross-sectional study of percentual changes in total plasmatic fatty acids during pregnancy.

Total plasma fatty acids were analysed in 75 first trimester pregnant women, 32 second trimester pregnant women, 27 women at delivery and 38 non-pregnant women. Eleven fatty acids were studied by capillar gas chromatography SP-column. Compared with non-pregnant women, in the first trimester there was a significant percentual increase in palmitic, palmitoleic, stearic and docosahexaenoic acids, whereas linoleic and eicosapentaenoic percentually decreased. Between the first and second trimester a significant increase in the proportion of palmitic acid and a significant percentual decrease in arachidonic acid was detected. Between the second trimester and delivery the aforementioned changes were more marked. Between the second trimester and delivery there was also a significant percentual increase in oleic and linolenic acids, whereas the proportions of stearic, linoleic, dihomogammalinolenic and docosahexaenoic acids significantly decreased. It is suggested that the intake in polyunsaturated fatty acids should be increased during pregnancy, specially in the third trimester.