Intrauterine programming of nephron number: the fetal flaw revisited

A broad range of epidemiological evidence supports the hypothesis that risk of essential hypertension, coronary heart disease and non-insulin dependent diabetes is, in part, determined before birth. This phenomenon, termed programming, is now the subject of intensive investigation in order to determine possible underlying mechanisms. It is widely accepted that maternal nutritional status in pregnancy is a major programming influence upon the fetus. This review considers the hypothesis that nephron number in humans is determined by prenatal nutrition. An increasing number of human studies indicate that the developing kidney is particularly vulnerable to the adverse effects of fetal growth retarding influences. In animals, growth retarding diets or other insults which have an impact upon the development of cardiovascular functions, also appear to impact upon nephron number. However, it is possible that hypertension and reduced renal reserve merely coincide and are not causally associated.