Evidence suggesting an effect of fetal growth on liver development and function stems from both animal and human studies. The association of birthweight with adult markers of liver damage and function was examined in a random sample of 2101 British women aged 60-79 years. Age-adjusted natural logged levels of alanine aminotransferase (ALT) and gamma glutamyltransferase (GGT) decreased linearly across increasing thirds of birthweight. Alkaline phosphatase (ALP) levels were higher in women of the lowest third of the birthweight distribution compared with other women. No evidence was found for associations of birthweight with aspartate aminotransferase (AST), total bilirubin and albumin. After full adjustment for social class, physical activity, smoking and alcohol consumption, an increase in one standard deviation of birthweight (691 g) was associated with a 2% ([95% CI 0%, 4%], P = 0.021) decrease in the geometric mean of ALT, a 4% decrease in GGT ([95% CI 1%, 6%], P = 0.008) and a 2% decrease in ALP ([95% CI 0%, 3%], P = 0.001). Associations of birthweight with ALT and GGT, but not with ALP, were attenuated when adjusting for components of the metabolic syndrome. These findings suggest that factors affecting intrauterine growth may increase the propensity for adult liver damage. The attenuation of associations with adjustment for components of the metabolic syndrome is in line with non-alcoholic fatty liver disease, indicated by elevated ALT and GGT, being the hepatic manifestation of the metabolic syndrome, and of the influence of perinatal factors on this syndrome.