Maternal pre-pregnancy BMI was increased (mean ± SD; 30.7 ± 5.6 kg/m2), 128 women had pre-pregnancy obesity, and 96 were diagnosed with GDM in the indexed pregnancy (including 36 on metformin or insulin): 61 in first trimester, 32 in second trimester, and three in third trimester. This evidence concerns the gene INS and gestational diabetes.