Possible association between hyperthyroidism in pregnant women and obstructive congenital abnormalities of urinary tract in their offspring--a population-based case-control study.
OBJECTIVE
The teratogenic potential of some antithyroid drugs is known, but the aim of the study was to estimate the risk of congenital abnormalities (CAs) in the offspring of pregnant women with hyperthyroidism with or without antithyroid drug treatment.


METHODS
Comparison of the occurrence of medically recorded hyperthyroidism who had malformed fetuses/newborns (cases) and who delivered healthy babies (controls) in the population-based Hungarian Case-Control Surveillance System of CAs, 1980-1996. Of 22,843 cases with congenital abnormalities, 71 (0.31%) while of 38,151 controls, 116 (0.30%) had mothers with hyperthyroidism. The rate of hyperthyroidism in the mothers of cases with different CAs and in the mothers of matched controls was compared.


RESULTS
Preeclampsia-eclampsia occurred more frequently in pregnant women with hyperthyroidism without antithyroid treatment. The analysis of specific groups of CAs showed an association between hyperthyroidism in pregnant women and obstructive defects of urinary tract in their children.


CONCLUSIONS
The lack of appropriate treatment of pregnant women affected with hyperthyroidism seems to be the major problem, because it would be necessary to prevent the hyperthyroidism related risks of pregnancy complications and CAs which exceed the risk of antithyroid medication in these pregnant women.
Bánhidy
Ferenc
F
Second Department of Obstetrics and Gynecology, Semmelweis University, School of Medicine, Budapest, Hungary.
Puhó
Erzsébet H
EH
Czeizel
Andrew E
AE
D000014:Abnormalities, Drug-Induced / Q000453:epidemiology / Q000209:etiology; D000328:Adult; D013956:Antithyroid Agents / Q000009:adverse effects / Q000627:therapeutic use; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006814:Hungary / Q000453:epidemiology; D006980:Hyperthyroidism / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D007231:Infant, Newborn; D011159:Population Surveillance; D011247:Pregnancy; D011248:Pregnancy Complications / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology; D037841:Pregnant People; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced / Q000453:epidemiology; D014524:Urethral Obstruction / Q000139:chemically induced / Q000151:congenital / Q000453:epidemiology*; D014551:Urinary Tract / Q000002:abnormalities*; D014570:Urologic Diseases / Q000151:congenital* / Q000453:epidemiology*; D055815:Young Adult
D013956:Antithyroid Agents