Objective:To analyze the relationship among thyroid autoimmunity (TAI), thyroid function, and gestational diabetes mellitus (GDM) in early pregnant women in Xi'an.Methods:A prospective study included pregnant women who underwent prenatal check-ups at the Northwest Women's and Children's Hospital from November 2020 to October 2021, with a gestational age of 6 to 14 weeks. Thyroid function, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), and urinary iodine levels were measured, and the prevalence of thyroid disease and GDM was monitored. The subjects were divided into four groups: TPOAb positive only, TgAb positive only, both TPOAb and TgAb positive, and both TPOAb and TgAb negative, to compare the differences in the prevalence of thyroid disease and GDM among the groups. Statistical analysis was performed using Kruskal-Wallis rank-sum test, Bonferroni correction, Chi-square test, and a multivariate logistic regression model was used to analyze the relationship between TAI, thyroid disease, and GDM. Results:A total of 20 243 early pregnant women were included in this study, among which 1 615 (7.98%) were positive for TPOAb only; 865 (4.27%) were positive for TgAb only; 1 672 (8.26%) were positive for both TPOAb and TgAb (both positive group); and 16 091 (79.49%) were negative for both TPOAb and TgAb (both negative group). The thyroid stimulating hormone levels in the TPOAb positive only group, TgAb positive only group, and both positive group were significantly higher than those in the both negative group, respectively (Bonferroni correction, all P<0.05); the free thyroxine level in the TPOAb positive only group was significantly lower than that in the both negative group ( P<0.05). After adjusting for age, pre-pregnancy body mass index, and urinary iodine levels, multivariate logistic regression analysis showed that compared to the both negative group, the risk of developing hypothyroidism during pregnancy was significantly increased in the both positive group ( OR=11.49, 95% CI: 2.84-46.39); the risk of developing subclinical hypothyroidism during pregnancy was significantly increased in the TgAb positive only group ( OR=1.99, 95% CI: 1.05-3.76) and the both positive group ( OR=3.74, 95% CI: 2.49-5.63); the risk of developing GDM was significantly increased in the TgAb positive only group ( OR=1.43, 95% CI: 1.04-1.96) and the both positive group ( OR=1.94, 95% CI: 1.53-2.46). Among early pregnant women with normal thyroid function, after adjusting for age, pre-pregnancy body mass index, and urinary iodine levels, multivariate logistic regression analysis showed that compared to the both negative group, the risk of developing GDM was significantly increased in the TgAb positive only group ( OR=1.46, 95% CI: 1.06-2.02) and the both positive group ( OR=1.80, 95% CI: 1.40-2.32). Conclusion:TgAb positive only is a risk factor for subclinical hypothyroidism and GDM. Screening for thyroid autoantibodies, especially TgAb, during pregnancy helps in the early identification of high-risk pregnant women for thyroid dysfunction and GDM.

Objective:To analyze the relationship among thyroid autoimmunity (TAI), thyroid function, and gestational diabetes mellitus (GDM) in early pregnant women in Xi'an.Methods:A prospective study included pregnant women who underwent prenatal check-ups at the Northwest Women's and Children's Hospital from November 2020 to October 2021, with a gestational age of 6 to 14 weeks. Thyroid function, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), and urinary iodine levels were measured, and the prevalence of thyroid disease and GDM was monitored. The subjects were divided into four groups: TPOAb positive only, TgAb positive only, both TPOAb and TgAb positive, and both TPOAb and TgAb negative, to compare the differences in the prevalence of thyroid disease and GDM among the groups. Statistical analysis was performed using Kruskal-Wallis rank-sum test, Bonferroni correction, Chi-square test, and a multivariate logistic regression model was used to analyze the relationship between TAI, thyroid disease, and GDM. Results:A total of 20 243 early pregnant women were included in this study, among which 1 615 (7.98%) were positive for TPOAb only; 865 (4.27%) were positive for TgAb only; 1 672 (8.26%) were positive for both TPOAb and TgAb (both positive group); and 16 091 (79.49%) were negative for both TPOAb and TgAb (both negative group). The thyroid stimulating hormone levels in the TPOAb positive only group, TgAb positive only group, and both positive group were significantly higher than those in the both negative group, respectively (Bonferroni correction, all P<0.05); the free thyroxine level in the TPOAb positive only group was significantly lower than that in the both negative group ( P<0.05). After adjusting for age, pre-pregnancy body mass index, and urinary iodine levels, multivariate logistic regression analysis showed that compared to the both negative group, the risk of developing hypothyroidism during pregnancy was significantly increased in the both positive group ( OR=11.49, 95% CI: 2.84-46.39); the risk of developing subclinical hypothyroidism during pregnancy was significantly increased in the TgAb positive only group ( OR=1.99, 95% CI: 1.05-3.76) and the both positive group ( OR=3.74, 95% CI: 2.49-5.63); the risk of developing GDM was significantly increased in the TgAb positive only group ( OR=1.43, 95% CI: 1.04-1.96) and the both positive group ( OR=1.94, 95% CI: 1.53-2.46). Among early pregnant women with normal thyroid function, after adjusting for age, pre-pregnancy body mass index, and urinary iodine levels, multivariate logistic regression analysis showed that compared to the both negative group, the risk of developing GDM was significantly increased in the TgAb positive only group ( OR=1.46, 95% CI: 1.06-2.02) and the both positive group ( OR=1.80, 95% CI: 1.40-2.32). Conclusion:TgAb positive only is a risk factor for subclinical hypothyroidism and GDM. Screening for thyroid autoantibodies, especially TgAb, during pregnancy helps in the early identification of high-risk pregnant women for thyroid dysfunction and GDM.