Medical experts are drawing attention to a testicular issue that may affect up to one in five men.
Known as varicoceles, the condition is relatively common, with estimates suggesting it occurs in around 15 to 20 percent of men. In certain cases, it may also play a role in problems with male fertility.
A varicocele develops when a vein — or a network of veins — within the scrotum becomes enlarged. This can interfere with the environment sperm need in order to develop properly.
According to the NHS, these enlarged veins are more frequently found on the left side of the scrotum, although they can appear on either side.
The NHS Milton Keynes University Hospital explains: “It is not certain what causes varicocele. It is possible that a valve defect in the veins may be causing the veins to widen. Varicocele is not always visible but it does affect the blood flow in the testicles.
“If it becomes enlarged, it could cause the testicles to shrink and possibly reduce your fertility. Varicocele repair may improve fertility, but this is not guaranteed.”
Urologist Professor Suks Minhas told the Metro that there are symptoms men should look out for, including ‘pain and discomfort in the left testicle’.
He also pointed out that symptoms begin on the left side in the vast majority of cases, affecting roughly 90 percent of men with the condition.
Professor Suks added: “Other common sensations may include a dull or aching pain, swelling, and testicular atrophy. Larger varicoceles have also been described as feeling like a bag of worms or twisted veins.”
That said, he noted that some men may not notice any symptoms at all.
On the question of whether varicoceles can contribute to infertility, Professor Ramsay told the Metro that the issue is essentially that the condition can end up ‘heating the testicle’ — which can affect fertility.
“This happens because there is more blood around the testicle because the veins are dilated and distended, and the flow of the blood is coming from above in the abdomen, where the blood is warmer,” Professor Ramsay said.
“Testicles are in the scrotum because they like around 3°C below core temperature. But varicoceles warm the testicles and in so doing, causes oxidative stress.”
Oxidative stress may allow damaging chemicals to interact with seminal fluid, potentially lowering sperm quality.
Professor Ramsay also suggested varicoceles might ‘disturb some of the other functions of the testicles’.
With appropriate treatment, those functions may return closer to normal, depending on the individual case.