The left testicular vein is the male equivalent of the ovarian vein.
Both testicles have veins that attach at different locations. The right testicular vein attaches to the inferior vena cava. The left vein drains into the left renal vein.
The left testicle is bigger than the right one; therefore, the left vein is longer than the right. Because the left vein is longer, it is subject to more difficulties when draining. Poor drainage can lead to pathological conditions such as testicular swelling and pain.
There are also clinical consequences related to the left vein of the testicle and its connection to the left renal vein; kidney infections and even cancer of the kidney can spread to the left testicular vein. This causes the blood to gather, leading to dilated (expanded) veins in the scrotum.