Between 1977-1990, 755 women were evaluated and treated for ovarian cancer at the University of Miami/Jackson Memorial Medical Center. Ninety-five of them (12.6%) had previously undergone hysterectomy with preservation of one or both ovaries. Sixty women (7.9%) had undergone hysterectomies after the age of 40. Review of the literature reveals a 4.5-14.1% incidence of prior hysterectomy in women developing ovarian cancer. Prophylactic oophorectomy in women undergoing hysterectomy at age 40 or older would have prevented 138 of 2632 cases (5.2%) of ovarian cancer in a combined literature series. Applied nationally, such an approach could be expected to prevent over 1000 cases of ovarian cancer annually. We recommend routine prophylactic oophorectomy in all women undergoing hysterectomy after the age of 40. This strategy would have prevented 60 cases of ovarian cancer treated at the University of Miami during the past 14 years.