In addition, the levels of fetal insulin-like growth factor-binding protein-1 (IGFBP-1) were elevated in PM; this molecule negatively regulates IGFs expression and is associated with placental insufficiency (Shibuya et al., 2011; Umbers et al., 2011; Nawathe et al., 2016). The gene discussed is IGFBP1; the disease is placental insufficiency.