Major Gestational Trophoblastic Neoplasia risk factors include advanced maternal age and history of previous GTD.
Advanced maternal age
This is the highest risk factor for the development of GTD. Women over the age of 35 have a significantly increased risk of GTD; as many as 50% of pregnancies in women greater than age 50 are molar pregnancies.
History of previous GTD
A ten-fold increase in risk of GTD is observed if a woman has had a prior molar pregnancy (1% vs. 0.1%). That risk increases to 20-25% if a woman has had two or more molar pregnancies.
Smoking more than 15 cigarettes per day is associated with an increased risk of GTD.
History of infertility
Maternal blood type AB, A, or B.