Clinical prediction model for gestational diabetes mellitus utilizing thyroid function indicators: a retrospective cohort study

Background Our objective is to explore the relationship between gestational diabetes mellitus (GDM) and thyroid hormones, and construct a clinical prediction model based on the clinical features of GDM and thyroid parameters. Methods A population-based retrospective cohort study, including 1,035 GDM patients and 4,194 healthy control. Statistical tests were conducted to evaluate the associations between primary risk factors, including age, family history of diabetes, gestational hypertension, hypertension family history, thyroglobulin antibody (TGAb), and thyroid hormones (TT3, TSH, FT3, TPOAb), with GDM risk. Results In this study, age, family history of diabetes, gestational hypertension, hypertension family history, and TGAb concentration were identified as primary risk factors. The first four risk factors showed a positive associated with GDM, while height and TGAb concentration were significantly negatively correlated with GDM risk. Additionally, lower levels of total triiodothyronine (TT3) were associated with an increased risk of GDM in all patients, while consistently lower levels of thyroid-stimulating hormone (TSH) also heightened GDM risk. In the TGAb-negative group, higher levels of TT3 and TSH were linked to reduced risk of GDM, whereas lower levels of free triiodothyronine (FT3) were associated with an increased risk. In the TGAb-positive group, thyroid peroxidase antibody (TPOAb) had a strong positive association with GDM. Conclusions Thyroid hormones play a crucial role in pregnancy and may counteract insulin, affecting blood glucose balance. Therefore, changes in thyroid parameters should be appropriately considered in the prevention and screening of GDM.