Objective: Presentation of the incidence of cleft lip with or without cleft palate in the Czech Republic during 1961 to 2000. Design: Retrospective demographic epidemiological study. Setting: Institute for the Care of Mother and Child in Prague (period 1961–1990) were used as well as data from the nationwide registration of birth defects of infants ensured by the Institute of Health Information and Statistics of the Czech Republic covering the period 1987–2000. Epidemiological analysis of the incidence of cleft lip with or without cleft palate diagnosed in the Czech Republic during 1961–2000. Mathematical statistical analysis of the prevalence of these defects by maternal age, the method of calculation of the 95% confidence limit of probability was used. Results: From a consecutive series of 5 589 888 births in the CR during 1961–2000 a 1166 cases of cleft lip, 5052 caes of cleft lip and palate were diagnosed and 3970 cases of cleft palate. A total of 10 188 caes of facial clefts were recorded. The mean incidence of cleft lip was during the investigation period 2.09 per 10 000 liveborn infants, the incidence of cleft lip with/without cleft palate 11.13 per 10 000 liveborn infants. The mean incidence of cleft palate during the investigation period was 7.10 per 10 000 liveborn infants and of facial clefts as a whole 18.23 per 10 000 liveborn infants. Conclusion: The authors provided evidence that the frequency of facial clefts as a whole during the investigation period did not undergo significant changes as regards the trend of incidence. When evaluating maternal age as one of the risk factors for the development of facial clefts the investigation confirmed a greater risk in 15-year-old women and women older than 35 years without exception, in the group aged 29–84 years with the exception of 32.32 and 34 years (liminal findings).

        Key words: congenital defect, cleft lip with or without cleft palate, cleft palate, incidence, Czech Republic, maternal age