title: Applicability of the third-generation, thyroid-stimulating hormone assay in pregnancy.
abstract: Use of the third-generation, thyroid-stimulating hormone (TSH) assay in gravid patients has not been validated. We obtained serum from 93 healthy women with a singleton gestation and measured TSH using a two-site immunochemiluminescent ("sandwich") assay. Standard immunoassays were employed for total T4, free T4, and T3 levels. Reference ranges (RR) established by the kit manufacturer were used for comparison. Although the mean TSH level for our population was within the RR, 12/93 women (13%) had a TSH value below the lower limit of normal. None, however, had clinical hyperthyroidism or an elevated free T4. Established RR for the third-generation TSH assay may not apply to pregnant women, and isolated TSH measurements during pregnancy should be interpreted with caution.
authors.affiliation: Department of Obstetrics and Gynecology, Indiana University Medical Center/Indiana University School of Medicine, Indianapolis 46202, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Bobrowski
authors.forename: P
authors.initials: P
authors.lastname: Streicher
authors.forename: J S
authors.initials: JS
authors.lastname: Dzieczkowski
authors.forename: M P
authors.initials: MP
authors.lastname: Dombrowski
authors.forename: B
authors.initials: B
authors.lastname: Gonik
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008163:Luminescent Measurements; D008499:Medical Records; D011247:Pregnancy / Q000097:blood*; D012016:Reference Values; D012189:Retrospective Studies; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine