NON-MODIFIABLE RISK FACTORS   MODIFIABLE RISK FACTORS    Gender   Age   Personal breast cancer history   Family history   Proliferative breast conditions   Breast density > Early menstruation/ Late menopause    Radiation exposure   Reproduction   Breastfeeding   Hormone replacement therapy   Oral contraceptives   Body weight   Physical activity   Alcohol use   Tobacco smoke (for younger women)

EARLY MENSTRUATION/LATE MENOPAUSE

Women who experience their first period at an early age (before age 12) are more likely to develop breast cancer. As well, women who enter menopause at a late age (after age 55) are more likely to develop breast cancer.

The higher risk associated with early menstruation and late menopause is believed to result from the longer exposure to hormones at the levels that are present during child-bearing years.