A varicocele is a collection of widened veins, like varicose veins, that occurs on the outside of the testicle. A varicocele usually affects only the left testicle, although only the right, or both testicles, can be affected.
Usually the varicocele causes no symptoms, apart from a swelling on the outside of the testicle that may be noticeable when standing. It is sometimes described as feeling like a bag of worms. Occasionally it may cause an aching discomfort or a feeling of fullness in the testicle.
A varicocele is thought to occur because of the greater distance that the main vein from the left testicle travels inside the body (compared to the vein from the right testicle) before emptying into its respective kidney vein. This further distance, combined with the downward force of gravity, can in some men cause failure of the valve system somewhere between the vein from the left testicle and left kidney vein. As a result, blood pools in the small veins of the left spermatic cord, widening them and forming the swelling that is the varicocele.
To diagnose a varicocele a doctor will need to look at and feel the testicles. The varicocele can be felt through the scrotum as a swelling on the outside of the testicle — the so-called bag of worms. Often the varicocele can only be felt when a man is standing, and disappears when he is lying down as the blood pressure to it falls.
Some doctors may use an instrument placed on the outside of the scrotum to measure the temperature of the testicle. As a varicocele is thought to increase the temperature of the testicle, this instrument may be used to help detect an early varicocele, before it has become an apparent swelling on the testicle.
Up to 20 per cent of all men have a varicocele, but up to 40 per cent of men who have fertility problems have a varicocele. Until recently, having a varicocele was thought to contribute to difficulty in a man fathering children. Today, however, many doctors are not so certain that having a varicocele is a definite cause of fertility problems (see below).
A varicocele can be repaired by minor surgery in which the swollen veins are ligated (‘tied off’). Other techniques that close the swollen veins, for example, the injection of a chemical directly into the affected veins to seal them (sclerotherapy), may also be used.
If a man has a varicocele but has no discomfort and no fertility problems, then treatment may not be necessary. Wearing an athletic support may relieve aching in the affected testicle. However, if there is ongoing discomfort then surgery to correct the varicocele may be offered.
If a man with a varicocele is seeking treatment with his partner for difficulty in conceiving a baby, then, depending on the couple’s circumstances — and especially whether or not any other causes of the infertility have been diagnosed — a doctor may want to discuss repair of the varicocele.
For many decades having a varicocele was thought to reduce a man’s chances of fathering a child. For one thing, infertile men are much more likely to have a varicocele than fertile men. There have been reports that the warm blood pooling in the varicocele results in a raised temperature in the scrotum leading to abnormalities such as a low sperm count.
In terms of treating a varicocele to reverse fertility problems, however, a Cochrane review of men from subfertile couples, where the only abnormality found was a varicocele in the man, found no evidence that treatment of the varicocele with surgery or embolisation improved pregnancy rates. The Cochrane Collaboration is an international organisation aimed at helping people make well-informed decisions about healthcare by undertaking scientific reviews of evidence for certain treatments.
Other scientific reviews of the evidence have concluded that it is not known whether surgical ligation, embolisation or sclerotherapy of varicoceles increase pregnancy rates in affected couples.
In a teenage boy diagnosed with a varicocele, surgery is usually considered only if one testicle is considerably smaller than the other, or he is in pain. In cases where the affected testicle is smaller that the other testicle, catch-up testicular growth has been observed after repair. The boy or his family may choose to have the varicocele repaired because they believe it will minimise his chances of fertility problems later in life. Whether varicocele repair in adolescence actually does improve the sperm count or adult fertility remains unclear.
If you have a varicocele, it is very important to discuss treatment with your doctor or urologist in terms of your individual circumstances.
NOTE. If you have any swelling of your testicles, it is important to have it checked by a doctor straight away.
Last Reviewed: 30 September 2009