title: Choanal atresia associated with maternal hyperthyroidism treated with methimazole: a case-control study.
abstract: Thyrotoxicosis affects 0.2% of pregnant women and antithyroid drugs are the treatment of choice during pregnancy. Several case reports have suggested a relationship between the prenatal use of methimazole (MMI) and choanal atresia in the offspring. However, two epidemiological studies did not find an increased teratogenic risk for MMI. This multicenter case-control study compared the frequency of maternal hyperthyroidism treated with MMI during pregnancy, in children with choanal atresia (cases) and a control group randomly selected (three matched controls according to maternal age for each case). Mothers of cases (N = 61) and controls (N = 183) were interviewed for socio-demographic questions, obstetrical and genetic history, and exposure during pregnancy to different agents; specifically detailed information regarding hyperthyroidism and MMI intake was obtained. Prenatal exposure to maternal hyperthyroidism treated with MMI was identified in 10/61 cases (16.4%) compared to 2/183 (1.1%) in the control group (OR = 17.75; CI95% = 3.49-121.40). Cases and controls did not differ in their parental degree of education, paternal occupation, twinning, maternal parity, and other exposures during pregnancy. Facial features in exposed cases showed some similarities. Our data suggest that prenatal exposure to maternal hyperthyroidism treated with MMI is associated with choanal atresia. In addition, based on our cases and a critical literature review, we propose that the mother's disease might be the causal factor and not the MMI treatment.
authors.affiliation: Centro Nacional de Genética Médica, ANLIS, Ministerio de Salud, Buenos Aires, Argentina. pablobarbero63@hotmail.com
authors.forename: Pablo
authors.initials: P
authors.lastname: Barbero
authors.forename: Rita
authors.initials: R
authors.lastname: Valdez
authors.forename: Hugo
authors.initials: H
authors.lastname: Rodríguez
authors.forename: Carlos
authors.initials: C
authors.lastname: Tiscornia
authors.forename: Enrique
authors.initials: E
authors.lastname: Mansilla
authors.forename: Adriana
authors.initials: A
authors.lastname: Allons
authors.forename: Silvia
authors.initials: S
authors.lastname: Coll
authors.forename: Rosa
authors.initials: R
authors.lastname: Liascovich
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000453:epidemiology*; D000293:Adolescent; D013956:Antithyroid Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001118:Argentina / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002754:Choanal Atresia / Q000139:chemically induced* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D018811:Maternal Exposure; D008713:Methimazole / Q000009:adverse effects* / Q000627:therapeutic use; D011247:Pregnancy; D013971:Thyrotoxicosis / Q000188:drug therapy*
chemical_list: D013956:Antithyroid Agents; D008713:Methimazole