UMBILICAL VESSEL WALL FATTY-ACIDS AFTER NORMAL AND RETARDED FETAL GROWTH

In a prospective observational study, the fatty acid content of human umbilical artery and vein wall phospholipids was determined in fetuses classified according to their change in abdominal circumference durin g the third trimester. Three groups were identified: appropriate for g estational age (AGA; 24 infants) and small for gestational age (SGA; 3 8 infants) with normal antenatal growth rate, and SGA with fetal growt h retardation (22 infants). The venous linoleic acid (18:2 omega 6) co ntent (expressed as a percentage of the total fatty acids identified) was greater in growth retarded SGA fetuses (3.5 (0.6)%) than in SGA fe tuses with a normal growth rate (3.1 (0.5)%) and AGA fetuses (3.0 (0.5 )%), whereas the venous contents of eicosatrienoic (20:3 omega 6) and docosahexaenoic acid (22:6 omega 3) were lower. In growth retarded SGA fetuses, the venous and arterial 20:3 omega 6 content correlated with the change in abdominal circumference. In SGA fetuses with a normal g rowth rate, lower contents of arterial 18:2 omega 6 and 22:6 omega 3 w ere associated with a smaller change in abdominal circumference and bi rth weight. Different metabolic derangements appear to underly normal and subnormal growth rate in SGA fetuses, suggesting that different st rategies of dietary intervention may be required to aid fetal growth a nd reduce the sequelae of fetal growth retardation.