Rethinking Oocyte Yield in Advanced Maternal Age: Toward Age- and Biology-Calibrated Counseling Targets in IVF.

This Commentary examines whether the longstanding concept of an "optimal" oocyte number applies equally to women of advanced reproductive age undergoing IVF. Evidence from randomized trials and real-world datasets shows that the relationship between oocyte yield and cumulative live birth rate (CLBR) is strongly age-dependent, with older women often requiring higher oocyte numbers to achieve comparable cumulative outcomes due to biological constraints not captured in current dosing algorithms. RCTs and meta-analyses in predominantly young, homogeneous populations show fresh live birth rates peaking at 8-14 oocytes and CLBR plateauing at 20-25 oocytes, forming the basis of AMH- and weight-based individualized dosing strategies; however, these datasets underrepresent women ≥ 38 years and lack ancestry diversity. This Commentary synthesizes mechanistic biology, randomized trials, registry-level analyses, and population-specific studies across multiple regions. Across products and populations, higher oocyte yield improves CLBR up to a plateau that shifts rightward with age. Advanced reproductive age is characterized by higher aneuploidy, steeper developmental attrition, and lower OHSS risk, supporting evaluation of age-specific oocyte targets. Limitations include sparse RCT data in women ≥ 38 years and incomplete understanding of ancestry-specific modifiers. Age- and population-specific oocyte targets may help refine future individualized dosing algorithms and clinical decision-making.