Detection of Thyroid Dysfunction in Early Pregnancy: Universal Screening or Targeted High-Risk Case Finding?

Context: Maternal subclinical hypothyroidism during pregnancy is associated with various adverse outcomes. Recent consensus guidelines do not advocate universal thyroid function screening during pregnancy but recommend testing high-risk pregnant women with a personal history of thyroid or other autoimmune disorders or with a family history of thyroid disorders. Objective: The objective of the study was to assess efficacy of the targeted high-risk case-finding approach in identifying women with thyroid dysfunction during early pregnancy. Design/Setting: This was a single-center cohort study. Patients/Outcome Measures: We prospectively analyzed TSH, free T4 and free T3 in 1560 consecutive pregnant women during their first antenatal visit (median gestation 9 wk). We tested thyroperoxidase antibodies in 1327 (85%). We classified 413 women (26.5%), who had a personal history of thyroid or other autoimmune disorders or a family history of thyroid disorders, as a high-risk group. We examined whether testing only...