All cells in a eukaryote are diploid, except for germ cells. Germ cells (gametes) have only half the number of chromosomes as a diploid cell—one of each pair—and are termed haploid (n). In a human egg or sperm, there are 23 chromosomes, one of which is an X or Y. The number of chromosomes is reduced from 46 to 23 during the process of meiosis. Fertilization of the egg by the sperm restores the diploid number of 46 chromosomes.
I should also clarify from your question that fertilization does not result from two ova; rather, it is an ovum and sperm.