Triploidy is one of the rare chromosomal abnormalities that is caused due to the presence of an extra set of chromosomes. It is known to be the third fatal chromosomal anomaly. The majority of the conceptions are thought to be spontaneously aborted in their first trimester. A fetus that suffers from triploidy has a total of 69 chromosomes.
This happens due to three reasons: either because of the failure in the meiosis 1 or II in the spermatocyte or oocyte which results in an extra set of paternal or maternal chromosomes respectively or due to the phenomenon of dispermy in which a single ovum is fertilized with two sperms.
