Abstract
BACKGROUND: Fertility preservation is crucial for females facing gonadotoxic treatments. Controlled ovarian stimulation (COS) followed by oocyte cryopreservation is a well-established method, while ovarian tissue-derived oocyte in vitro maturation (OTO-IVM) is an emerging technique that can be used when COS is contraindicated or time is limited. However, OTO-IVM faces challenges such as low oocyte maturation rates and limited follow-up data. This study aimed to compare the clinical outcomes of COS oocyte cryopreservation and OTO-IVM, with a focus on the impact of transportation methods and the use of gonadotropin (Gn) before oophorectomy on OTO-IVM outcomes. METHODS: This retrospective study analyzed data from 472 patients who underwent fertility preservation procedures at the Reproductive Medicine Research Center, The Sixth Affiliated Hospital, Sun Yat-sen University, from July 2012 to July 2024. Patients diagnosed with cancer or requiring gonadotoxic treatments were included. The study compared oocyte maturation, fertilization, and embryo transfer outcomes between COS and OTO-IVM groups. Statistical analyses were performed using Student's t-test for continuous data and Chi-squared or Fisher's exact test for categorical data, with significance defined as P < 0.05. RESULTS: COS group resulted in a significantly higher oocyte maturation rate (86.11%) compared to OTO-IVM group (39.43%). Direct oocyte transport yielded a higher rate of denuded oocytes compared to ovarian tissue transport. The use of Gn before oophorectomy in OTO-IVM significantly improved the IVM maturation rate (51.90% vs. 38.00%, P < 0.001). CONCLUSIONS: COS oocyte cryopreservation remains more effective than OTO-IVM. However, the study highlighted the importance of optimizing transportation methods and using Gn before oophorectomy to improve OTO-IVM outcomes. These findings could guide clinical practice in selecting appropriate fertility preservation strategies. Further research is needed to refine OTO-IVM techniques and enhance their clinical applicability.