Outcomes of Fertility Preservation for Female Cancer Patients in a Single Tertiary Center

To report our experience of fertility preservation (FP) in female cancer patients. We retrospectively analyzed the medical records of female who underwent elective oocyte or embryo cryopreservation before cancer treatment between January 2015 and December 2020 at Asan Medical Center. We analyzed the type of cancer, the rate of reuse of cryopreserved oocytes or embryos, and fertility outcomes such as the resumption of menstruation or pregnancy. A total of 174 patients underwent 182 oocyte retrieval cycles after controlled ovarian stimulation for oocyte or embryo cryopreservation. The median age of patients was 33.0 (range 19-46) years, and the patients were most unmarried female (65.52%). The majority of patients were diagnosed with breast cancer (78.16%), and the remaining were diagnosed with gastrointestinal (6.33%) and hematologic malignancies (5.75%). The maturation rate of oocyte cryopreservation was 83.33%, and the fertilization rate of embryo cryopreservation was 72.07%. Of the 57 patients currently not undergoing cancer treatment, 34 resumed menstruating and 19 (33.33%, 19/57) returned to attempt a pregnancy. Among them, five patients succeeded in natural pregnancy. Eleven patients received frozen-thawed embryo transfer, and four patients succeeded in becoming pregnant (36.36%, 4/11). Only 6.3% of patients returned to use their gametes, and 93.7% of gametes are still in storage. FP in cancer patients should be considered before cancer treatment. Through continuous research on oncofertility, it is necessary to consider how to increase the return rate and provide appropriate information to cancer patients of reproductive age.