PON1 and gestational diabetes: The women with GDM also had significantly higher fasting glucose and insulin concentrations, HOMA-IR, TG, TG/HDL-C ratios, TOS, TAC and MDA levels, and PON1 lactonase activities and tended to have increased PON1 levels compared with the control women after adjusting for the difference in age and BMI at delivery (Table 2).