Periods Clue to Breast Cancer Onset, University of Oxford Study  
10/18/2012 8:00:09 AM

The younger a woman starts her periods, and the later she finishes, the more at risk she is from developing breast cancer. Now a new study led by Oxford researchers shows that these factors are particularly relevant for specific types of breast cancer. The findings reveal more about the way female sex hormones are linked to risk of breast cancer.