Etiology and pathogenesis of varicocele: contemporary perspectives and clinical significance

Abstract

Varicocele is a common vascular disorder characterized by abnormal dilatation and tortuosity of the pampiniform venous plexus within the spermatic cord. Affecting approximately 15% of the general male population and up to 35–40% of men with primary infertility, varicocele represents one of the most significant correctable causes of male reproductive dysfunction. The etiology of varicocele is multifactorial, involving anatomical predisposition, venous valve insufficiency, increased hydrostatic pressure, and genetic susceptibility. Contemporary research emphasizes the complex interplay between hemodynamic alterations and molecular mechanisms contributing to testicular injury. Pathogenetic pathways include scrotal hyperthermia, oxidative stress, hypoxia, hormonal imbalance, and disruption of the blood–testis barrier. Elevated reactive oxygen species levels and impaired antioxidant defense systems result in sperm DNA fragmentation, mitochondrial dysfunction, and apoptosis of germinal epithelium. Chronic venous stasis further promotes microcirculatory disturbances and inflammatory responses, exacerbating spermatogenic impairment. Emerging data also suggest potential epigenetic modifications influencing reproductive outcomes. Despite high prevalence, the clinical course varies, with many cases remaining asymptomatic while others progress to infertility or testicular hypotrophy. Understanding etiological factors and molecular mechanisms is essential for early risk stratification and targeted therapeutic intervention. This review synthesizes modern scientific evidence on the origin and biological mechanisms of varicocele and highlights its clinical implications for male reproductive health and long-term fertility preservation.