Both the maternal and fetal somatotrophic axes are closely linked to fetal substrate supply. Nutritional insults at critical stages of fetal development may lead to permanent reprogramming of the relationships between these factors. The consequences of reprogramming during fetal life may be harmful to metabolic, endocrine and cardiovascular homoeostatic mechanisms in postnatal life. The exact mechanisms that lead to reprogramming during fetal life need thorough investigation before effective strategies to deal with this problem can be devised.