Importancia de mantener una suficiente concentración sérica de T4 materna en el primer trimestre del embarazo

The maternal endocrine system is essential for optimal fetal development, and normal endocrine mechanisms are temporarily supplanted during pregnancy. Transplacental transfer of thyroid hormone plays a crucial role in fetal neurodevelopment throughout ontogeny, especially before mid-gestation when fetal thyroid synthesis becomes significant. Thus, normal maternal thyroid hormone function is essential, ensuring adequate thyroid hormone and iodine levels throughout pregnancy. Epidemiological and experimental studies have robustly shown that maternal hypothyroxinemia in the first trimester of pregnancy increases the risk for adverse neurodevelopmental and neuropsychological outcomes in offspring.