An embryo with more or fewer than the normal 46 chromosomes. It is naturally occurring in early human embryos is due to miss location of chromosomes during meiosis in either egg or sperm. It may occur after fertilization during mitosis. Most of the aneuploidy embryos failed to implant or get arrested at morulla stage. If, they get implanted it will result to miscarriage or the baby will be suffering from drown syndrome or other genetic disorders.