Low MASP-2 and high GUDCA (i.e., >0.07 nmol/mL) used as the reference, the copresence of high MASP-2 and low GUDCA (i.e., ≤0.07 nmol/mL) enhanced the ORs of high MASP-2 alone and low GUDCA alone, respectively, from 12.2 (1.59–93.1) and 11.9 (2.33–60.4) up to 37.6 (6.92–204.6) for GDM. This evidence concerns the gene MASP2 and gestational diabetes.