In addition, studies found that there were some differences in pathogenesis between obese and nonobese GDM women (2, 33, 40), and in our study, the FGF21 levels of the obese GDM subgroup were significantly higher than those of normal BMI GDM subgroup, which suggested that the mechanism of FGF21 resistance might be different in GDM women with different BMIs. Here, FGF21 is linked to gestational diabetes.