The causes of hydatidiform mole are related to problems with fertilization during reproduction. The tumors are created through abnormal fetal development or when cells that normally make the tissue of the placenta become abnormal, but the exact process is not known.
Several risk factors for hydatidiform mole may be contributing causes but increase the chances of getting molar pregnancy very little. These include:
- diets low in protein, fat and vitamin A
- age – most often affecting women of childbearing age
- an earlier molar pregnancy
- prior miscarriages
- A or AB blood types, compared to B or O blood types
Birth control pills could raise the risk of hydatidiform mole although it is unclear if other factors may be involved. However, in general the benefits offered by birth control pills exceed the small increased risk of a molar pregnancy. A higher risk for the condition seems to exist for women with lower incomes, possibly related to dietary issues.