GPT and gestational diabetes: Women with high levels of GGT and ALT had increased ORs for the development of GDM + IT not only in obese women (OR 6.348, 95% CI 2.579–15.625), but also in non-obese women (OR 3.05, 95% CI 1.565–5.946) when compared to women without obesity and with low enzyme levels (Fig. 2 and Supplementary 1).