Incompetent or inadequate valves within the veins along the spermatic cord cause a varicocele. The abnormal valves obstruct normal blood flow causing a backup of blood, resulting in enlargement of the veins. Varicoceles usually develop slowly and usually have no symptoms. Varicoceles are a common cause of infertility in men.
Review Date 7/31/2019
Updated by: Sovrin M. Shah, MD, Assistant Professor, Department of Urology, The Icahn School of Medicine at Mount Sinai, New York, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.