title: Thyroid disease in the perinatal period.
abstract: BACKGROUND
  Thyroid hormone plays a critical role in fetal development. In pregnancy, increased thyroid hormone synthesis is required to meet fetal needs, resulting in increased iodine requirements.
  
  
  OBJECTIVE
  This article outlines changes to thyroid physiology and iodine requirements in pregnancy, pregnancy specific reference ranges for thyroid function tests and detection and management of thyroid conditions in pregnancy.
  
  
  CONCLUSIONS
  Thyroid dysfunction affects 2-3% of pregnant women. Pregnancy specific reference ranges are required to define thyroid conditions in pregnancy and to guide treatment. Overt maternal hypothyroidism is associated with adverse pregnancy outcomes; thyroxine treatment should be commenced immediately in this condition. Thyroxine treatment has also been shown to be effective for pregnant women with subclinical hypothyroidism who are thyroid peroxidase antibody positive. Gestational thyrotoxicosis needs to be differentiated from Graves disease and rarely requires thionamide treatment. Postpartum thyroiditis most commonly presents with isolated hypothyroidism but a biphasic presentation and isolated hyperthyroidism can occur: a high index of suspicion is warranted for diagnosis.
authors.affiliation: Royal Melbourne Hospital and the Royal Women's Hospital, Victoria, Australia. forehan@gmail.com
authors.forename: Simon
authors.initials: S
authors.lastname: Forehan
mesh_terms: D013956:Antithyroid Agents / Q000627:therapeutic use; D001323:Autoantibodies / Q000097:blood; D001324:Autoantigens / Q000276:immunology; D005260:Female; D006801:Humans; D007453:Iodide Peroxidase / Q000276:immunology; D007455:Iodine / Q000172:deficiency / Q000627:therapeutic use; D033862:Iron-Binding Proteins / Q000276:immunology; D008403:Mass Screening; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis* / Q000188:drug therapy*; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D013959:Thyroid Diseases / Q000175:diagnosis* / Q000188:drug therapy*; D013960:Thyroid Function Tests; D013974:Thyroxine / Q000627:therapeutic use
chemical_list: D013956:Antithyroid Agents; D001323:Autoantibodies; D001324:Autoantigens; D033862:Iron-Binding Proteins; D019275:Radiopharmaceuticals; D007455:Iodine; C056658:TPO protein, human; D007453:Iodide Peroxidase; D013974:Thyroxine