Intrauterine growth restriction affects concentrations of growth factors and hormones.32, 37 Low levels of IGF-1 and/or of insulin-like growth factor-binding protein 3 (IGFBP-3) in the fetal blood have been described.38 Therefore, the alterations of these factors and maternal arterial resistance may contribute to the impairment of placental circulation during growth restriction. Here, IGF1 is linked to fetal growth restriction.