An incorrect number of
chromosomes is the most common form of genetic disorder that causes the fetus
to spontaneously abort. The
human cells normally contain 23 pairs of chromosomes, for a total of 46
chromosomes in each cell. Error in one or more of the meiosis, mitosis,
maternal age, or environment are the possible cause of the chromosome
abnormalities. These abnormalities in the number chromosomes can cause problems
with development, growth and function of the body's systems. These changes can
occur in early fetal development, or in any cell after birth during the
formation of reproductive cells (sperm and eggs).