Objective: Analysis of incidences of congenital malformations (CM) in prenatal and postnatal diagnostics in the Czech Republic in 2001 and a comparison to the years 1994-2000. Design: A retrospective demographic-epidemiological study. Setting: Institute for Care of Mother and Child, Prague. Methods: Analysis of incidences ofCMand chromosomal aberrations in live- and stillbirths and their number in prenatally diagnosed cases in teh Czech Republic in 2001. Data On CM incidences were obtained form those registered in statistical reports (CM in a fetus or a child) collected through the Institute of Health Information and Statistics of the Czech Republic (UZIS). Data available by the end of October 2002 were analysed.Supplementary data on prenatal diagnostics cases were obtained from particular departments of medical genetics in the Czech Republic. Results: Therewere 90,715 livebirths in 2001 compared to 90,910 livebirths in 2000. The total number of children with CM in 2001 was 3,572 additional 457 cases were diagnosed prenatally and the pregnancies were terminated, whereas in 2000, 3,751 children withCMwere born and 425 cases were diagnosed prenatally (and pregnancies were terminated). Conslusion: Data analysis from theCMregistration in the Czech Republic has continued also in 2001 due to a good collaboration with both UZIS and paticular departments of madical genetics. The total number of registered CM cases in livebirths is increasing in the last years, despite of prenatal diagnostics techniques level, which is comparable to the level in the most advanced countries.

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