Introduction and Problem: Since the introduction of in vitro fertilization (IVF) there has been continuing discussion on possible genetic defects and malformations in children in connection with the technique of assisted reproduction. These data have not been so far analyzed in the all- -state scale of the Czech Republic and our contribution thereby contributes by present complex analysis of the data to the knowledge of this problem in this country. Material and Methods: The paper analyzes data of children from IVF Registry for the years 1995- 1998 and compares the results obtained with those of children born after spontaneous pregnancy in the Czech Republic in the period of 1995-1999. The incidence of inborn defects in children born after IVF methods has been confronted with data from the VV Registry after spontaneous conception. It is a retrospective analysis of individual anonymous data. Results: In the period of 1995-1998 there were 3.782 successful pregnancies after IVF, which ended by successful delivery of the children. In the period of 1995-1999, 367735 children were born in the Czech Republic on the whole. In the total number of 3.782 successful pregnancies, 5.126 children were born, 5.108 being born alive and were stillborn. The frequency of children having been delivered with an inborn defect were 2.98 % in the IVF children and 2.77% in other born children, the difference not being statistically signifi cant. Conclusion: The analysis of our cohort of IVF children has not revealed increased rate of inborn defects in comparison with children born after spontaneously conception.

        Key words: assisted reproduction, genetic defect, malformations