The Incidence of Congenital Defects in the Descendants ofMothers Taking Medication in the First Trimester in the CzechRepublic in the Period of 1996 – 2001

Overview

Objective:
Analysis of the results from registration of congenital defects in children of motherstaking therapeutic drugs in the fi rst trimester of pregnancy and comparison with a control groupin the Czech Republic in the period of 1996-2001.Design: A retrospective analysis of data from the registry of congenital defects in the CzechRepublic.Setting: Institute for the Care of Mother and Child, Prague.Methods: Analysis of incidences of selected types of congenital defects detected in newbornsof mothers taking therapeutic drugs during the fi rst three months of pregnancy. The paperemployed data from the all-state registration of congenital defects held in the Institute of MedicalInformation and Statistics of the Czech Republic in the period of 1996 – 2001. Data from healthychildren born to mothers who took therapeutic drugs during the fi rst trimester of pregnancywere used as a control set.Results: In the period we observed, a total of 17,674 cases of children with diagnosed congenitaldefect were detected in the registration of congenital defects in the Czech Republic. In thisnumber there were 784 cases of children whose mothers used therapeutic drugs during thefi rst trimester of pregnancy. The control group included 1,034 women who gave birth to healthychildren without congential defects, although they took therapeutic drugs during the fi rsttrimester of pregnancy. Statistically signifi cantly higher risk was found in 13 groups of diagnoses:anencephaly, inborn hydrocephalus, spina bifi da, inborn defects of eyelids, lacrimal system andorbita, anoftalmus, microphthalmus and macrophthalmus, inborn defects of ear, congenitaldefects of the heart septum, congenital defects of great veins, cleft palate with cleft lip, congenitaldefect of gall bladder, biliary pathways and liver, congenital deformities of the hip, reductiondeformities of upper extremity, congenital defects of muscular and skeletal system.Signifi cantly higher risks were found for fi ve groups of therapeutic drugs: anticoagulants,antihypertensive drugs, peripheral vasodilatants, urological drugs and antiepileptic drugs.Conclusion: It is obviously impossible to draw signifi cant conclusions with clinical consequenceson the basis of these results. Nevertheless, our results supplemented international databasesof untoward effects of drugs and the conclusions may become a part of data set necessary foranalysis of possible teratogenic effects of drugs used in the critical developmental period duringthe fi rst trimester. The pregnant women should avoid, during the fi rst trimester, all drugsexcept those, which are carefully medically indicated and accepted as adequately safe. Theadministration of other drugs should be evaluated by a clinical geneticist, who should take intoaccount genetic and teratogenic risk in individual cases.

Key words:
congenital defect, population teratology, teratogen, incidence, Czech Republic