RESUMO
Background The association between hypothyroidism and iron-deficiency anemia (IDA) in pregnancy is not well established. Hence, this study aimed to investigate the association between hypothyroidism and IDA during the first trimester of pregnancy. Methodology In this study, a total of 144 pregnant women were included. Thyroid-stimulating hormone (TSH), free T4 (FT4), free T3 (FT3), and ferritin were measured. Based on TSH values, pregnant women were divided into the following two groups: euthyroid (n = 74) and hypothyroid (n = 70). Results There was a significant increase in TSH levels and a significant decrease in the levels of FT4, FT3, ferritin, iron, and hemoglobin (Hb) in hypothyroid pregnant women compared to euthyroid pregnant women. The correlation and regression analysis revealed a significant negative association of TSH and a positive association of FT4 with ferritin, iron, and Hb. Conclusions These findings demonstrate the association of hypothyroidism with IDA during the first trimester of pregnancy. Further studies with thyroxine therapy in hypothyroid pregnant women and its impact on IDA will open novel therapeutic approaches in the management of IDA during pregnancy. Further, measurement of serum ferritin during pregnancy may provide valuable information in the diagnosis and management of IDA.