Posthemithyroidectomy Pregnancy Thyroid Function Surveillance: Frequency, Adherence, and Guideline Impact

Posthemithyroidectomy women are at an increased risk for gestational subclinical hypothyroidism. Therefore, the American Thyroid Association (ATA) recommends increased thyroid function surveillance for this subgroup of pregnant women. The purpose of this study was to evaluate the frequency of thyroid function surveillance during pregnancy in posthemithyroidectomy women and to evaluate the adherence to the 2017 ATA guidelines and its possible impact since being published on thyroid function surveillance rates. A retrospective study of pregnant posthemithyroidectomy women operated at our institution between 1997 and 2020 was performed. The study cohort was subdivided by pregnancy dates before 2018 and 2018 onward to evaluate the impact of the 2017 ATA guidelines. Adherence to the guidelines was defined as at least 1 thyroid-stimulating hormone test in each trimester. After exclusions, a total of 120 pregnancies conceived by 66 women who underwent hemithyroidectomy surgeries were included in this study. Overall, serum thyroid-stimulating hormone examinations were performed during the first, second, and third pregnancy trimesters in 86.6%, 40%, and 16.6% of pregnancies, respectively (P