Objective: Presentation of the incidence of selected types of birth defects in registers of birth defects abroad and in comparison with data from the Czech Republic in 1988–1998. Design: Retrospective epidemiological analysis of the incidence of birth defects. Setting: Institute for the Care of Mother and Child, Prague. Methods: Analysis of the incidence of 15 types of selected birth defects in liveborn and stillborn infants in 1988–1998 according to published data and publications of the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS) and European Registration of Congenital Anomalies (EUROCAT). Comparison of the incidence of 15 selected types of congenital defects from 24 registers worldwide incl. the Czech Republic. Results: In the resultant incidences of selected types of congenital defects during the presented period participate geographical and ethnic differences as well as a series of other factors, in particular primary and secondary prevention of birth defects. The influence of other biosocial factors is assumed. Conclusion: Long-term well functioning registration of birth defects is an essential prerequisite not only for national analyses but also for possible more detailed collaboration and analyses on an international scale.

        Key words: data from registers, most frequent congenital defects, regional differences in incidence of development defects