The role of the intrauterine environment in the later development of type 2 diabetes and the metabolic syndrome

Abstract

Links between indices of poor fetal growth and either adult type 2 diabetes, the metabolic syndrome, or both are reproducible in many studies and many ethnic groups. It has been proposed that genetic factors, environmental factors, or a mixture of both underlie these links. Studies of monozygotic twins have shown that environmental factors operate independently of the genome. Attention has been focused recently on links with childhood growth, particularly rapid catch-up growth before puberty. Animal models have shown that poor maternal nutrition can lead to glucose intolerance and hypertension in offspring. The molecular mechanisms mediating these links are unclear. The hypothalamic–pituitary–adrenal axis may be involved as may the sympathetic nervous system. It is difficult to calculate what proportions of type 2 diabetes and metabolic syndrome may be caused by early environmental factors. Conversely, it is possible to obtain a low figure.