In BRCA1/2 gene mutation carriers, a risk-reducing salpingo-oophorectomy (RRSO) is recommended around the age of 40. This recommendation is based on a 10-40% life-time risk of ovarian cancer in this population and disappointing results of ovarian cancer surveillance for early detection. Moreover, the mortality rate of ovarian cancer is high. Effects of RRSO are a decrease in ovarian cancer risk (80-96%) on one hand and immediate onset of menopause and non-cancer related morbidity on the other hand. The fifty percent breast cancer risk reduction after RRSO has become disputable in the last years. Based on multiple studies showing that most high-grade serous ovarian cancers develop at the distal end of the Fallopian tube, an innovative strategy for RRSO has been developed for this study proposal: risk-reducing salpingectomy (RRS) with delayed risk-reducing oophorectomy (RRO). However, the safety of this strategy has not been proven yet. Before implementing this innovative strategy as standard care we need to investigate the long term effects on ovarian cancer incidence.