Intrauterine

growth restriction is a relatively common condition that results in disproportionately high perinatal morbidity and mortality (Knutzen and Sher, 1982; Newton et al., 1987). Intrauterine growth restriction may be classified clinically on the basis of a birth weight below the tenth percentile for gestational age or, in experimental studies, as a fetal body weight below two standard deviations of the mean of the relevant study population. A range of pathophysiological factors can result in a perturbation or restriction of fetal growth, including gene defects, chromosomal abnormalities, poor placental function, maternal smoking, maternal alcohol or drug abuse and altered maternal substrate concentrations (Robinson et al., 1994). The specific physiological adaptations of the fetus to an adverse intrauterine environment, includin