The spermatic veins emerge from the back of the testis, and receive tributaries from the epididymis: they unite and form a convoluted plexus, the plexus pampiniformis, which forms the chief mass of the cord.
In addition to its function in venous return from the testes, the pampiniform plexis also plays a roles in the temperature regulation of the testes. It acts as a heat exchanger, cooling blood in adjacent arteries.
The vessels composing this plexus are very numerous, and ascend along the cord in front of the ductus deferens; below the subcutaneous inguinal ring they unite to form three or four veins, which pass along the inguinal canal, and, entering the abdomen through the abdominal inguinal ring, coalesce to form two veins.
These again unite to form a single vein, the testicular vein, which opens on the right side into the inferior vena cava, at an acute angle, and on the left side into the left renal vein, at a right angle.
- Template:SUNYAnatomyLabs - "Inguinal Region, Scrotum and Testes: Veins"
- Histology image: 17304ooa – Histology Learning System at Boston University - "Male Reproductive System: spermatic cord, pampiniform plexus"
- Template:OklahomaHistology - "Spermatic cord"
- Diagram at rutgers.edu