What are the breast cancer screening guidelines in Canada (Ontario)?

Every province has its own guidelines, although they are all similar. The Ontario Breast Screening
Program screens two different groups of women for breast cancer; those women at average risk and
those at high risk for developing breast cancer. Women with an average risk are recommended to have
a mammogram every 2 years between age 50 to 74. High risk women between the ages 30 to 69 are
recommended to be screened annually with both mammography and breast MRI or breast ultrasound.