title: Malformations following methimazole exposure in utero: an open issue.
abstract: BACKGROUND
  In hyperthyroidism-complicated pregnancies, medical therapy is necessary to reach an euthyroid condition, and propylthiouracil (PTU) or methimazole (MMI) are used. These drugs are equally effective, but may cause fetal and neonatal hypothyroidism because they freely cross the placenta. Although PTU has not been significantly associated with embryo-fetal anomalies, it has been suggested that MMI might be responsible for a specific embryopathy.
  
  
  METHODS
  Two cases of major congenital anomalies after MMI exposure during pregnancy are reported.
  
  
  CONCLUSIONS
  PTU should be the drug of choice, and the use of MMI should be restricted to cases with allergic reactions, intolerance, or poor response to PTU.
authors.affiliation: Dipartimento di Scienze Pediatriche, Università di Torino, Turin, Italy.
authors.forename: Silvio
authors.initials: S
authors.lastname: Ferraris
authors.forename: Mariella
authors.initials: M
authors.lastname: Valenzise
authors.forename: Margherita
authors.initials: M
authors.lastname: Lerone
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Divizia
authors.forename: Lucia
authors.initials: L
authors.lastname: Rosaia
authors.forename: Dario
authors.initials: D
authors.lastname: Blaid
authors.forename: Odette
authors.initials: O
authors.lastname: Nemelka
authors.forename: Giovanni Battista
authors.initials: GB
authors.lastname: Ferrero
authors.forename: Margherita
authors.initials: M
authors.lastname: Silengo
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000209:etiology*; D013956:Antithyroid Agents / Q000627:therapeutic use*; D004476:Ectodermal Dysplasia / Q000209:etiology*; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000188:drug therapy*; D007231:Infant, Newborn; D008297:Male; D008423:Maternal Age; D008713:Methimazole / Q000627:therapeutic use*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000188:drug therapy*; D018566:Pregnancy, High-Risk; D012535:Scalp / Q000002:abnormalities; D014427:Twins
chemical_list: D013956:Antithyroid Agents; D008713:Methimazole