title: Thyroid function tests and thyroid autoantibodies in an unselected population of women undergoing first trimester screening for aneuploidy.
abstract: BACKGROUND
  Thyroid dysfunction in early pregnancy is associated with a number of adverse outcomes. Furthermore, the presence of thyroid autoantibodies has been associated with an increased risk of miscarriage.
  
  
  OBJECTIVE
  To determine the prevalence of thyroid autoantibodies and their effect on thyroid function tests in an unselected population of women in early pregnancy.
  
  
  METHODS
  Cross-sectional study of samples that were collected for aneuploidy screening between 10 and 14 weeks gestation in Northern Sydney Area Health Service. Thyroid function tests (free T3, free T4 and thyroid-stimulating hormone) and thyroid autoantibodies to thyroperoxidase and thyroglobulin were measured.
  
  
  METHODS
  Thyroid function tests were performed on a random sample of 257 blood samples.
  
  
  RESULTS
  The presence of thyroid autoantibodies was common (18.3%) and was associated with subtle changes in thyroid function consistent with impaired thyroidal reserve.
  
  
  CONCLUSIONS
  The prevalence of antithyroid Abs in an unselected pregnant population in the late first trimester was about 18%.
authors.affiliation: Department of Endocrinology, Royal North Shore Hospital, and Department of Obstetrics and Gynaecology, University of Sydney, St Leonards, Sydney, New South Wales, Australia. aidanm@med.usyd.edu.au
authors.forename: Aidan
authors.initials: A
authors.lastname: McElduff
authors.forename: Jonathan
authors.initials: J
authors.lastname: Morris
mesh_terms: D000328:Adult; D000782:Aneuploidy; D001323:Autoantibodies / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis; D011261:Pregnancy Trimester, First / Q000097:blood / Q000276:immunology; D015995:Prevalence; D013959:Thyroid Diseases / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000276:immunology* / Q000502:physiology*; D013972:Thyrotropin / Q000097:blood / Q000276:immunology; D013974:Thyroxine / Q000097:blood / Q000276:immunology; D014284:Triiodothyronine / Q000097:blood / Q000276:immunology
chemical_list: D001323:Autoantibodies; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine