A new study released in Lancet Oncology showed that abnormal levels of female hormones in the bloodstream may be why women with BRCA1 or BRCA2 mutations are at a higher risk for breast and ovarian cancer and not other cancers.  UCL Department of Women’s Cancer completed the study that found different levels of the female hormones oestradiol and progesterone in women with BRCA1 or BRCA2.