title: Influence of female sex hormones on thyroid parameters determined in a thyroid screening.
abstract: This is a cross-sectional study with a non-randomly selected population to ascertain the influence of female sex hormones on thyroid function. TSH, TT4, FT4, TT3 and FT3 were determined in 251 women using either oral hormonal contraceptives or hormone replacement treatment, 255 women not taking either, and a control group of 900 men. Women with normal thyroid morphology using oral hormonal contraceptives in the pre-menopausal group had a significantly higher TT4 and TT3, and lower FT3, respectively, than both non-users and men. FT4 and TSH remained unchanged. In the peri-/post-menopausal group, thyroid function of women using hormone replacement treatment was not significantly different from non-users, but either women still had a significantly lower FT3 than men. We conclude that oral hormonal contraceptives and hormone replacement treatment increase TT4 and TT3 and do not influence FT4 and TSH. They decrease FT3 which is in contrast to what would be expected theoretically and what has been observed in earlier studies.
authors.affiliation: Department of Nuclear Medicine, Carl Gustav Carus Medical School, University of Technology, Fetscherstrasse 74, D-01307 Dresden, Germany. Thomas.Gruning@phnt.swest.nhs.uk
authors.forename: Thomas
authors.initials: T
authors.lastname: Grüning
authors.forename: Klaus
authors.initials: K
authors.lastname: Zöphel
authors.forename: Gerd
authors.initials: G
authors.lastname: Wunderlich
authors.forename: Wolf-Gunter
authors.initials: WG
authors.lastname: Franke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003278:Contraceptives, Oral, Hormonal / Q000494:pharmacology*; D003430:Cross-Sectional Studies; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000187:drug effects*; D013972:Thyrotropin / Q000187:drug effects; D013974:Thyroxine / Q000187:drug effects*; D014284:Triiodothyronine / Q000187:drug effects*; D014463:Ultrasonography
chemical_list: D003278:Contraceptives, Oral, Hormonal; D011933:Reagent Kits, Diagnostic; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine