Varicoceles are not life-threatening, however, they can be linked to serious illnesses in rare cases. If a varicocele arises on the right side of the abdomen rather than the left, for example, make sure there is no mass or other abnormalities in the abdomen that could be causing it. Blood is transported back to the heart via veins throughout the body. They usually feature valves to keep the blood flowing in the right way. When the valves in the testicular vein don't work properly, blood can pool in the scrotum, resulting in a varicocele. They commonly happen on the left side, and they're caused by the testicular vein's path through the abdomen.