Relationship Between Serum 25(OH)D Level and Thyroid Function in Gestational Diabetes Mellitus Patients

XU Ting; ZHANG Yuling; LI Taoying

doi:10.3969/j.issn.1004-437X.2026.04.012

Abstract：Objective To investigate the relationship between serum 25-hydroxyvitamin D[25(OH)D]levels and thyroid function in patients with gestational diabetes mellitus(GDM).Methods Ninety-five cases of GDM patients in the Second Affiliated Hospital of Zhengzhou University from March 2021 to March 2023 were selected as the GDM group,and 50 cases of healthy pregnant women in the same period of obstetric examination were selected as the control group.General data of the enrolled pregnant women were collected,and serum 25(OH)D levels and thyroid function indexes[serum free triiodothyronine(FT3),thyroid stimulating hormone(TSH),thyroid peroxidase antibody(TPOAb),free thyroxine(FT4),thyro-globulin antibody(TGAb)]were detected in enrolled pregnant women from 24 to 28 weeks.Pearson correlation was used to analyze the relationship between serum 25(OH)D and TGAb and TPOAb.Results In the control group,1 case of noncompliance with biochemical testing was excluded,and 49 cases were included;in the GDM group,1 case of self-exit and l case of poor compliance were excluded,and 93 cases were included.There was no significant difference in the comparison of serum FT3,FT4,and TSH levels between the two groups(P＞0.05),but the expression levels of serum TGAb and TPOAb in patients in the GDM group were higher than those in the control group(P＜0.05).The serum 25(OH)D level of patients in the GDM group was lower than that of the control group(P＜0.05).Pearson correlation analysis showed that serum 25(OH)D was negatively correlated with TGAb(correlation coefficient r value=-0.475,95％CI:-0.593--0.336)and TPOAb(correlation coefficient r value=-0.606,95％CI:-0.701--0.490).Conclusion In GDM patients,serum 25(OH)D was under-expressed,TGAb and TPOAb levels were elevated,and there was a correlation between 25(OH)D and TGAb and TPOAb.