Furthermore, the Spearman’s rank coefficients between leptin levels and fasting insulin (rs = 0.53, P < 0.001), fasting plasma glucose (rs = 0.24, P < 0.001) and HOMA-IR (rs = 0.51, P < 0.001), QUICKI (rs = −0.51, P < 0.001) were mildly increased in GDM group, but reduced in NGT group (data not shown). Here, INS is linked to gestational diabetes.