Compare and contrast complete versus partial mole.

Complete mole is more aggressive than a partial mole; results from the abnormal fertilization of an ovum that does not have chromosomes. When fertilized by a sperm, the chromosomes from the father are duplicated; there is a normal number of chromosomes (46) but these are all from the father; no embryo develops, and the chorionic villi become cystic.
Partial mole is less aggressive than a complete mole; caused by fertilization of a normal ovum, resulting in three sets of chromosomes. Embryo forms but does not survive and the trophoblastic tissues becomes a mixture of normal and cystic villi.