Predictive Value of Vein Diameter Threshold and Clinical Factors in Semen Quality Improvement after Varicocelectomy

OBJECTIVE: To evaluate whether preoperative varicocele vein diameter predicts postoperative semen quality improvement after microsurgical varicocelectomy, to identify a threshold value, and to assess the influence of age and venous reflux on these associations. STUDY DESIGN: A descriptive cohort study. Place and Duration of the Study: Department of Urology, Manisa Celal Bayar University, Manisa, Turkiye, between June 2010 and August 2025. METHODOLOGY: A total of 108 men aged 18-40 years with unilateral left-sided varicocele who underwent subinguinal microscopic varicocelectomy for infertility were included; predefined exclusions were applied. Semen parameters [progressive motility, total sperm count, and Sperm Motility Index (SMI)] were averaged from two preoperative tests and compared with the best value at postoperative 6-12 months. The effects of vein diameter, age, and venous reflux on these outcomes were assessed using chi-squared, Mann-Whitney U, and Spearman tests. ROC analysis evaluated vein diameter as a predictor. A p-value of