Hi there
in North America here are the following statistics:
Women have a 1 in 80 lifetime risk of developing ovarian cancer.
Women have a 1 in 8 lifetime risk of developing breast cancer.
That is : breast cancer is 10 times more common than ovarian cancer.
Women with two or more first degree family members with ovarian cancer or who have personally tested positive for the BRCA 1 or 2 gene mutation have a higher risk of developing ovarian cancer. For this group of women at higher risk, the prophylactic surgical removal of the ovaries and fallopian tubes after completing child bearing is recommended.
best wishes
Did your grandmother and aunt both have ovarian cancer? If so, it is possible you have a BRCA mutation, which would put you at increased risk of both breast and ovarian cancer.