GSTM1 and gestational diabetes: After matching, significant differences remained in RBC count and Hb concentration (NGT vs. GDM, 116 ± 11 vs. 123 ± 10 g/L in T1, 110 ± 11 vs. 114 ± 9 g/L in T2, 109 ± 13 vs. 115 ± 12 g/L in T3, all P < 0.001) and blood glucose metabolic profiles, as well as delivery and neonatal outcomes (all P < 0.05) (Supplementary Tables S1, S2).