BTG3 and autoimmune thyroid disease: <h4>Objective</h4>To identify the relationship between thyroid autoimmunity and antinuclear antibody (ANA) prevalence in Chinese pregnant women.<h4>Methods</h4>The study involved 1923 first-trimester women who were measured for thyroid stimulating hormone (TSH) level, thyroid autoantibodies (thyroperoxidase antibody [TPOAb] and thyroglobulin antibody [TgAb]) and ANA titer.