The domestic cat is along with the dog recently the most common and popular pet. Unlike the dog the cat kept her appearance and nature without major changes despite long years of domestication. She has been highly adaptive to extremely variable conditions. Beeing a prolific species she breeds succesfully in wide range of enviromental conditions and in a large spectrum of climatic conditions from subarctic to tropical regions. She reproduces successfully in urban colonies in high density of thousands of cats per square kilometre as well as in arctic regions with the population density equal to one cat per square kilometre. Mating strategy varies from promiscuous behaviour, through polygyny/polyandry system, to monogamy. The infanticide in felinae is a common reproductive strategy. Male kills dependent offspring sired by another male in order to hasten the female oestrus and to reproduce with her himself. In domestic cats the infanticide attracts long-lasting discussion. However, in reality reports on the incidence of infanticide has been scarce. One of the possible female counter-strategies is pregnancy block, known as a Bruce effect. The mated female blocks the blastocyte implantation when facing the treath of possible infanticide to avoid waste of energy by delivering offspring with poor chance for survival. Based on the questionnaire survey we have estimated the possibility of reproduction failure in a situation of potential male infanticide. From data which we have obtained we could not yet check the advanced hypothesis due to lack of variation and very few recorded cases of reproduction failure. On the other hand, we have accumulated extended information of the cat reproduction. In the future we are planning to collect more data in order to be able to test properly the hypothesis.