Latrogenic infertility as a result of cancer treatment has a profound effect on long-term quality of life in survivors of reproductive-age cancers. Oocyte cryopreservation prior to cancer treatment has been associated with improved quality of life, with a potential ability to reduce long-term decision-related regret in cancer survivors. Though letrozole plus gonadotropin and and tamoxifen plus gonadotropin are currently routinely used worldwide in ovarian stimulation cycles for fertility preservation in patients with estrogen-receptor-positive breast cancer, it is not clear which of the two might lead to improved oocyte yield. Improved knowledge about the efficacy of these medications, with regard to oocyte yield, has the potential to significantly improve quality of life in reproductive-age breast cancer survivors.