In vitro maturation for fertility preservation in cancer patients: a systematic review and meta-analysis

To evaluate the effectiveness of in vitro maturation (IVM) of oocytes as a fertility preservation strategy compared to conventional approaches or no intervention in female cancer patients prior to gonadotoxic therapy, addressing maturation, fertilization, and long-term outcomes.

A systematic review and meta-analysis were conducted using JBI methodology. The PubMed, Scopus, and ClinicalTrials.gov databases were searched (January 2020 to July 2025; English only). Eligible studies included female cancer patients aged 15-45 years who had undergone IVM before cancer treatment. Data extraction and critical appraisal were performed in duplicates. Random-effects models were used for the meta-analysis, and heterogeneity and certainty were assessed using subgroup analyses.

Nine studies were included, of which six studies contributed to pooled maturation rate analysis. The pooled oocyte maturation rate was 35.9% (95% CI: 34.5-37.3%) and significantly higher post- versus pre-menarche (40.7% vs. 26.1%, p < 0.001). Fertilization rates averaged 65.5% (95% CI: 59.4-71.4%) overall and 68.3% in the cancer cohorts. Live birth data are scarce but encouraging. Protocol heterogeneity and limited long-term follow-up reduced the certainty.

IVM is a feasible option for urgent or hormone-sensitive fertility preservation in cancer patients, with maturation rates lower than controlled ovarian stimulation (COS) but comparable fertilization rates per mature oocyte. Standardized protocols and long-term outcome data are required to optimize the practice.