RESUMEN
To ensure patient care in an oncological fertility preservation (FP) programme, specialists must provide technology that best suits the patients' clinical conditions. In vitro oocyte maturation (IVM) and ovarian tissue cryopreservation (OTC) are possible fertility preservation treatments for women in need of urgent oncological treatment. IVM consists of the retrieval of immature oocytes from small antral follicles, with no or minimal ovarian stimulation by gonadotropins. Therefore, IVM has become a pertinent option for fertility preservation, especially for cases whereby ovarian stimulation is unfeasible or contra-indicated. Existing data on immature oocytes, retrieved transvaginally (OPU-IVM) or extracted from ovarian tissue 'ex vivo' (OTO-IVM), are still limited on technical consistency, efficacy, and safety. The present retrospective cohort study includes 89 women undergoing fertility preservation using IVM methodologies and 26 women undergoing ovarian stimulation (OS) in concomitant period. In total, 533 immature oocytes were collected from IVM patients, achieving a maturation rate of 57% and 70% in OTO-IVM and 73% and 82% in OPU-IVM at 24 h and 48 h in culture, respectively. The observed high maturation rates might be due to the use of patients' serum in its innate status, i.e., without heat-inactivation. This permitted 7.6 ± 5.7 and 4.6 ± 4.9 oocytes to be vitrified in OTO-IVM and OPU-IVM, respectively, compared to 6.8 ± 4.6 from OS patients. Regarding OS patients, two of them underwent embryo transfer following the insemination of warmed oocytes after complete remission, resulting in a single live birth from one patient. Upon follow-up of two OTO-IVM patients after the termination of their oncological treatment, a total of 11 warmed oocytes lead to a transfer of a single embryo, but pregnancy was not achieved. From OPU-IVM, six embryos were transferred in three patients 4.25 years after oocyte vitrification, leading to the live birth of a healthy boy. The present case of live birth is among the first cases reported so far and supports the notion that IVM might be a relevant and safe FP option for cancer patients when oocyte preservation is required but ovarian stimulation is contra-indicated.
RESUMEN
BACKGROUND: Freezing strips of ovarian cortex before chemotherapy followed by transplantation is an experimental method to preserve fertility for reproductive-aged women with cancer. We report a case of a cancer patient who developed a mucinous cystadenoma in a grafted piece of ovarian cortex. CASE: A 32-year-old woman with a Ewing sarcoma had ovarian cryopreservation using cortical strip freezing before receiving chemotherapy. Five years later she had no ovarian function, and the strips were thawed and grafted back onto the ovary. She spontaneously became pregnant 1 year after this procedure and delivered a healthy neonate near term. During the cesarean delivery, a 5×3-cm cyst was removed from the graft. On pathologic evaluation, it was determined to be a mucinous cystadenoma. CONCLUSION: Ovarian pathology can develop in previously frozen ovarian cortex tissue after transplantation back onto the ovary. This suggests that routine gynecologic surveillance remains important for these women.