number of chromosomes found in the embryo
The embryos created by human beings during the union of the sperm and the egg are supposed to have 46 total chromosomes. This is called the diploid state. The chromosomes are arranged in 23 pairs. They are number 1 through 22. The 23rd pair are not given a number, these are the sex chromosomes.
Less commonly, an embryo can contain an entire extras set of chromosomes. Instead of 46 chromosomes (2 copies of all 23 chromosomes), the embryo many contain 69 chromosomes (3 copies of all 23 chromosomes) This is called triploidy. There can also be tetraploidy for four sets and so on.