Hydatiform Mole Case# 22400 Hydatiform mole (sometimes referred to as a Molar Pregnancy) occurs when placental tissue takes over the pregnancy. It is possible to have a partial mole and fetus simultaneously. Patient HCG levels will usaully be extremely elevated in these cases and an increase in vascular flow may help with the diagnosis. A tetraploidy that has the same appearance is also available for review on this website.