Biomimetic Fibrin Matrix Modulates Early Human Follicular Growth Dynamics in a Bioengineered Artificial Ovary Derived from Cryopreserved Tissue: In Vitro Morphometric Assessment

Ovarian tissue cryopreservation is the primary fertility preservation strategy for prepubertal girls and patients requiring urgent gonadotoxic therapy. However, the risk of reintroducing malignant cells has prompted the development of safer alternatives, including follicle isolation followed by three-dimensional scaffold encapsulation for transplantation. Fibrin is a promising biomaterial for bioengineered ovary construction, although its ability to support early human follicle maintenance remains unclear. Follicles isolated from cryopreserved ovarian tissues of six patients were encapsulated within fibrin scaffolds of graded concentrations (high, medium, low). After 7 days of in vitro culture, follicle survival and diameter change were quantified. A total of 282 follicles (45.4 ± 10.1 µm) were embedded into fibrin scaffolds. After culture, 237 viable follicles were detected, yielding an overall survival of 84%. Follicle diameter increased to 58.8 ± 12.0 µm. Follicle survival rates were comparable across groups, while mean follicle diameter was 56.3 ± 12.5 µm (high), 61.9 ± 13.4 µm (medium), and 57.4 ± 9.3 µm (low). Follicles cultured in medium-concentration fibrin demonstrated significantly larger diameters compared with both high and low groups (p < 0.05), with no difference between high and low groups. Fibrin-based bioprosthetic ovary scaffolds support short-term in vitro maintenance of isolated human follicles, preserving spherical morphology and granulosa cell layer integrity. Medium-concentration fibrin was associated with greater follicle diameter expansion compared with higher and lower concentrations, indicating that scaffold composition influences early morphometric changes during in vitro follicle culture.