Advances, Mechanisms, and Clinical Perspectives for the In Vitro Maturation of Human Oocytes

The in vitro maturation (IVM) of human oocytes represents a valuable assisted reproductive technology that bypasses the need for full ovarian stimulation, offering safer alternatives for patients with polycystic ovary syndrome (PCOS), resistant ovary syndrome, or those requiring fertility preservation before oncological treatment. Despite its potential, IVM efficiency remains lower than that of conventional in vitro fertilization (IVF) due to incomplete understanding of the molecular and metabolic mechanisms underpinning oocyte maturation. This review summarizes recent advances in IVM, including biphasic or simulated physiological oocyte maturation (SPOM) systems, optimization of culture media through hormones, growth factors, and antioxidants, and the influence of cumulus-oocyte communication on developmental competence. We also discuss the biochemical regulation of meiosis, metabolic interactions, and gene expression patterns associated with oocyte quality. Furthermore, we examine the translational and clinical applications of IVM in human fertility treatment, highlighting its efficacy in PCOS and oncofertility cases, and the limitations that persist in replicating in vivo conditions. Emerging technologies such as microfluidic and three-dimensional culture systems show promise in enhancing oocyte competence and embryo yield. Continued research into the molecular mechanisms governing oocyte maturation will be key to improving IVM outcomes and integrating this approach as a mainstream option in reproductive medicine.