No associations of 25(OH)D measures, 1,25(OH)2D and PTH with GDM were observed in the logistic regression modelling (25(OH)D: crude odds ratio (OR) 1.00 (CI 0.99 to 1.01), adjusted OR 1.00 (CI 0.99 to 1.02); Free 25(OH)D: crude OR 1.00 (CI 0.95 to 1.05), adjusted OR 1.00 (CI 0.94 to 1.06); 1,25(OH)2D: crude OR 1.00 (CI 0.99 to 1.01), adjusted OR 1.00 (CI 0.99 to 1.01); PTH: crude OR 1.19 (0.92 to 1.52), adjusted OR 1.18 (CI 0.90 to 1.54)) (S3 and S4 Tables). Here, PTH is linked to gestational diabetes.