Relationship of hypothyroxinemia to gestational diabetes mellitus during early pregnancy

Objective To investigate the relationship of hypothyroxinemia to gestational diabetes mellitus during early pregnancy. Methods A total of 11 365 cases of women with early singleton pregnancies were collected from Chongqing Health Center for Women and Children. The screening of thyroid function was performed. The postload glucose concentrations and the risks of gestational diabetes mellitus in hypothyroxinemia were investigated. The relationship of thyroid hormones to postload glucose concentration was evaluated. The association between thyroid peroxidase antibodies(TPOAb)and gestational diabetes mellitus was analyzed. Results Early pregnancy women with hypothyroxinemia had a higher postload glucose concentration. Comparing to normal pregnancy women, the prevalence of gestational diabetes mellitus in hypothyroxinemia was higher(42.2%vs18.4%, P<0.05). Free thyroxine(FT4)was significantly negatively correlated with postload glucose concentration. FT4 was associated with gestational diabetes mellitus. The risk of gestational diabetes mellitus was greater when FT4 was lower. The prevalence of gestational diabetes mellitus in early pregnancy women with TPOAb levels ≥500 IU/ml was significantly higher than that in normal pregnancy women(31.2%vs 18.4%, P<0.05). Conclusion Early pregnancy women with hypothyroxinemia and TPOAb≥500 IU/ml were related to the risk of gestational diabetes mellitus. Lower FT4 was the risk factor of gestational diabetes mellitus. (Chin J Endocrinol Metab, 2017, 33: 194-197) Key words: Hypothyroxinemia; Gestational diabetes mellitus; Thyroid peroxidase antibodies