BGLAP and gestational diabetes: The serum 25-OH-D and BMD levels in the GDM group were lower than in the normal group, whereas the bone alkaline phosphatase (BALP), osteocalcin (OC), procollagen type I propeptide (PINP), and beta-isomerized C-terminal telopeptide (β-CTx) levels in the GDM group were significantly higher than in the normal group, with the differences showing statistical significance (p<0.05, respectively).