DIETARY-INTAKE AND TISSUE CONCENTRATION OF FATTY-ACIDS IN OMNIVORE, VEGETARIAN AND DIABETIC PREGNANCY

The aim of this study was to determine the effect of fatty acid intake and insulin dependent diabetes on the fatty acid composition of mater nal erythrocytes, the placenta and cord. Fatty acid intake (from food frequency questionnaire) and the fatty acid composition of maternal er ythrocytes, the placenta and cord from pregnant vegetarians (n = 4) an d insulin dependent diabetics (n = 5) was compared with pregnant omniv ores (n = 10). There was a significantly lower intake of n-6 long chai n polyunsaturated fatty acid (LCPUFA) (-75% P < 0.01) and n-3 LCPUFA ( -92% P < 0.01) and increased ratio of n-6/n-3 LCPUFA in the vegetarian s (103%; P < 0.001). The concentrations of 22:4 n-6 (+28%, P < 0.05) a nd 22:5 n-3 (+40%, P < 0.05) were higher in vegetarian erythrocytes. P lacental 18:2 n-6 (+26.9%; P < 0.05) 18:3 n-3 (+139%, P < 0.05) and 22 :5 n-3 (+24%, P < 0.05) were increased while 20:5 n-3 (-36%, P < 0.05) , 22:6 n-3 (-16%; P = 0.059), and the ratios of 20:4 n-6/18:2 n-6 (P < 0.01) and 22:6 n-3/18:3 n-3 were reduced. 22:6 n-6 (-49%, P < 0.05) a nd total n-3 LCPUFA (-11%; P < 0.01) were reduced in vegetarian cord. For the diabetic mothers, all of the n-6 LCPUFA and n-3 LCPUFA were re duced in the maternal erythrocytes; 22:4 n-6 (-42%; P < 0.05), 22:5 n- 6 (-46%, P < 0.05) and 22:6 n-3 (-41%, P < 0.05). For the diabetic pla centa and cord the general pattern of n-3 LCPUFA was the same as that in the vegetarians. In the vegetarian mothers, the PUFA profiles in th e maternal erythrocytes, placenta and cord are consistent with an elev ation in the rate of LCPUFA synthesis in order to make up the relative deficit in LCPUFA intake. However, it may be that the higher level of desaturase activity is not able to overcome the dietary deficit of 22 -6 n-3 and 22:6 n-6. Despite the fact that the dietary LCPUFA intake i n the pregnant diabetic was comparable with that in the pregnant 'norm al' omnivore mothers, the pattern of PUFA in the tissues resembled tha t of the vegetarian mothers.