This study aimed to determine the optimal TSH cut-off level for the diagnosis of SCH in the first trimester of gestation in our local clinical area, to determine the value of this TSH screening to predict the presence of positive TPO Ab, and to compare the prevalence of SCH using 2.5 mIU/L vs. both ATA 2017 and our locally specific cut-off points for TSH. Here, TPO is linked to spindle cell hemangioma.