The WHO 2025 Guideline for the Prevention, Diagnosis and Treatment of Infertility: A Comprehensive Review with Focus on Male Reproductive Health.

Infertility affects millions worldwide and is increasingly recognized as a major public-health concern. Despite advances in reproductive medicine, the lack of a unified global framework has contributed to substantial heterogeneity in clinical practice, particularly in the evaluation and management of male infertility. In 2025, the World Health Organization (WHO) issued its first comprehensive Guideline for the Prevention, Diagnosis, and Treatment of Infertility, establishing a global, evidence-based standard applicable across diverse resource settings. Notably, the guideline integrates male reproductive health throughout prevention, diagnosis, and treatment pathways, reinforcing the essential role of paternal factors in reproductive outcomes. This review summarizes the development, scope, and methodological foundations of the WHO guideline, including its use of systematic evidence synthesis, the GRADE framework, and structured consensus processes. Particular emphasis is placed on male-focused recommendations and good practice statements on lifestyle risk modification, sexually transmitted infections, standardized semen analysis, diagnostic algorithms, unexplained infertility, antioxidant supplementation, and varicocele repair. The review also clarifies the guideline's public-health scope and delineates areas that remain within the domain of specialty practice. Finally, we discuss dissemination, implementation challenges, and research priorities, highlighting persistent evidence gaps in male reproductive biology, sperm function, and clinically meaningful treatment outcomes. By aligning public-health principles with contemporary understanding of male physiology, the WHO guideline provides a global foundation for equitable and systematic infertility care.