The paper presents data on the incidence of birth defects revealed in born infants under the age of one year and prenatal diagnosis of birth defects in the Czech Republic in 1997 and a brief comparison with the previous period from 1992 - 1996. In the first part data on the total of birth defects are given, in the second part the authors compare the incidence of selected types of birth defects in 1997 with mean frequencies in 1961 - 1990. In the third part a comparison of perinatal and early neonatal mortality in the CR in 1997 with 1992 - 1996 is presented. The final part presents the results achieved in prenatal diagnosis in selected types of birth defects.

        Key words: birth defect, population teratology, incidence, Czech Republic (CR), prenatal diagnosis, secondary prevention, success