Varicocele is termed as an abnormal enlargement of a vein in the scrotum. Known to be one of the leading causes of infertility, Varicocele is a lifestyle disease – this means that Varicocele develops over the course of time. How does it lead to infertility? Well, the arterial and venous systems bring and send blood to and from the scrotum. This blood has to be pure for the good production of sperm. Now, when the venous system fails to send back the blood due to a Varicocele, there is more impure blood in the testis and this is bad for the production of sperm. Thus, the sperm count reduces eventually causing infertility in the long term.