Substantial medical evidence shows that about half of ovarian cancers originate in the fallopian tube. Some medical organizations and clinical articles have suggested opportunistic salpingectomy to reduce the risk of ovarian cancer in patients at average risk of developing it. This entails removing the fallopian tubes at the same time as another procedure that would occur anyway. The authors argue that the principles of totality and double effect can justify such salpingectomies, even though there is a low incidence of ovarian cancer. Since screening tools for ovarian cancer are ineffective and treatment options are poor, the good effect of reducing the risk of death from this type of ovarian cancer can be proportionate to the bad effects of the minor increase in surgical risk over the other procedure, the unintended side effect of infertility, and the removal of normally functioning tissue. The authors conclude that it is within the purview of a patient and physician to determine whether the benefits are proportionate to the risks in a particular case.