Sensitivity of mammography depends on menstrual phase

Mammography carried out in the second half of the menstrual cycle may miss breast cancer in women who have used oral contraception or hormone replacement therapy, a Canadian study shows.

Dr Cornelia Baines and her team from the University of Toronto examined data from the Canadian national breast screening study, which recruited 8887 menstruating women aged 40-44 years. They suggest that the higher risk of a false negative result on mammography …