Development of Testicular Veins
The reason that varicoceles develop can be seen from how the testicle develops (See animation on right).
When a foetus is developing before birth, the testicle grows up by the kidney.
As the baby grows, the testicle "descends" into the pelvis and then out into the scrotum. It takes its vein (the testicular vein) with it on this journey.
The two testicular veins are very long, and so are prone to suffer from valves to fail - causing blood to fall back into the veins which dilate under the backward flow - and a Varicocele is formed. |