German scientists claim to have found the cure for what is regarded the biggest cause of male infertility — blocked vessels in the testicle, reports BBC .

A simple surgical procedure can treat what some regard as a leading cause of male infertility, says a German team.

The team found that using a minimally invasive technique to correct blocked vessels in the testicle enabled some previously infertile men to conceive.

The findings were presented at the annual meeting of the Radiological Society of North America. But other experts said the results were not conclusive because the team had not carried out a control study.

Some researchers believe varicose veins in the testicle, varicoceles, are a leading cause of male infertility.

Varicoceles, which are a tangled network of blood vessels, are caused by blood circulation problems. They are relatively common: about 10-15% of men are estimated to have them.

Although in many cases they are harmless, some believe they can lead to fertility problems because they cause warm blood to pool, increasing the scrotum temperature and reducing sperm count.

Previous reviews of research have found that using open surgery to remove the varicoceles in sub-fertile men have not made any difference to their ability to conceive, but the researchers in Germany used a different technique called embolisation.

This involves inserting a small catheter into the groin and steering it into the varicocele. A tiny platinum coil and a special fluid are then injected, via the catheter, to block off the faulty vein, diverting the blood flow through an alternative route.