Worldwide it is estimated that 15% of couples have problems conceiving. A likely primary cause for poor germ cell quality is aneuploidy (a wrong number of chromosomes in the cell). Indeed, the vast majority of embryos formed from aneuploid gametes are non-viable and lead to spontaneous abortion. Our project aims at understanding the mechanisms that promote production of oocytes with a correct number of chromosomes, which is essential for the generation of viable and normal embryos and thus for successful reproduction. We use a multidisciplinary approach that combines genetics, cell biology, cutting edge microscopy technics and the use of the powerful model system Caenorhabditis elegans.