title: Treatment of subclinical hypothyroidism in pregnancy using fixed thyroxine daily doses of 75 μg.
abstract: OBJECTIVE
  Treatment of hypothyroid pregnant women is usually calculated based on weight (1 μg/kg/day) and TSH levels. This study assessed the usefulness of treating these women with a fixed dose of 75 μg/day.
  
  
  METHODS
  All women with pregnancy diagnosed from January to August 2012 in the Vigo Health Area (Spain) without previous diagnosis of thyroid disease or thyroxine treatment and with TSH levels over 4,5 mUI/ml were enrolled by consecutive sampling. All 116 women in the sample were treated with a fixed daily dose of thyroxine 75 μg-thyroxine levels were measured at two, four, and six months, and thyroxine dose was modified if TSH level was lower than 0.3 or higher than 4.5 mUI/ml.
  
  
  RESULTS
  A woman had a TSH level less than 0.3 mUI/ml in a test; reduction of thyroxine dose to 50 μg/day allowed for maintaining TSH level within the desired range until delivery. Six women had TSH levels over 4.5 mUI/ml in one test; in all of them, increase in thyroxine dose to 100 μg/day allowed for maintaining the level within the desired range until delivery.
  
  
  CONCLUSIONS
  Fixed daily doses of thyroxine 75 μg allowed for achieving goal TSH levels in most of our pregnant women with subclinical hypothyroidism, irrespective of their weight and baseline TSH level.
authors.affiliation: Servicio de Endocrinología y Nutrición, Complexo Hospitalario Universitario de Vigo, Vigo, Pontevedra, España. Electronic address: manuelpenin@wanadoo.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Penin
authors.affiliation: Servicio de Endocrinología y Nutrición, Complexo Hospitalario Universitario de Vigo, Vigo, Pontevedra, España.
authors.forename: Cristina
authors.initials: C
authors.lastname: Trigo
authors.affiliation: Servicio de Endocrinología y Nutrición, Complexo Hospitalario Universitario de Vigo, Vigo, Pontevedra, España.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: López
authors.affiliation: Servicio de Endocrinología y Nutrición, Complexo Hospitalario Universitario de Vigo, Vigo, Pontevedra, España.
authors.forename: María
authors.initials: M
authors.lastname: Barragáns
mesh_terms: D000328:Adult; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000188:drug therapy*; D013974:Thyroxine / Q000008:administration & dosage*
chemical_list: D013974:Thyroxine
keywords: Dose; Dosis; Gestación; Hipotiroidismo; Hypothyroidism; Pregnancy; Thyroxine; Tiroxina; Tratamiento; Treatment