Nutrition during pregnancy can impact on the susceptibility of the offspring to cardiovascular disease. Postnatal consumption of trans fatty acids (TFA), associated with partially hydrogenated vegetable oil (PHVO), increases the risk of atherosclerosis, while evidence for those trans fatty acids associated with ruminant-derived dairy and meat remain equivocal. Here, we investigate the impact of maternal consumption of dietary PHVO (P) and ruminant milk fat (R) on the development of atherosclerosis in their offspring, using the transgenic apoE*3 Leiden mouse. Dams were fed either chow (C) or one of three high fat diets: a diet reflecting the saturated fatty acid content of a ‘Western’ diet (W) or one enriched with either P or R. Diets were fed during either pregnancy alone or pregnancy and lactation. Weaned offspring were then transferred to an atherogenic diet for twelve weeks. Atherosclerosis was assessed as lipid staining in cross-sections of the aorta. There was a significant effect of maternal diet during pregnancy on development of atherosclerosis (p=0.013) in the offspring with those born of mothers fed R or P during pregnancy displaying smaller lesions that those fed C or W. This was not associated with changes in total or lipoprotein cholesterol. Continuing to feed P during lactation increased atherosclerosis compared to that seen in offspring of dams fed P only during pregnancy (p<0.001). No such effect was seen in those from mothers fed R (p=0.596) or W (p=901). We conclude that dietary TFA have differing effects on cardiovascular risk at different stages of the lifecycle
