Previous in vitro studies trying to mimic hyperglycaemic conditions of GDM in the human trophoblast cell line BeWo have shown an initial upregulation of DMT1 and Zrt- and Irt-like protein 8 (ZIP8/SLC39A8) after 3 days, followed by a stable downregulation of DMT1, FPN1 and TFR1 mRNA after 20 days of continued hyperglycaemia exposure [45]. Here, SLC40A1 is linked to gestational diabetes.