LEP and gestational diabetes: Table 3 shows the main characteristics of the articles on mRNA and/or protein levels in placenta and umbilical cord of TNF-α, leptin, apelin, NGAL, adiponectin, resistin, visfatin, omentin-1, fetuin A, RBP4, nesfatin-1, AFABP, vaspin, and irisin in GDM.