When the spermatic veins that lead upward from the testicles toward the heart become abnormally swollen, the one-way valves inside the veins fail and it becomes difficult for blood to be pumped uphill against gravity. The blood backs up in the veins around the testicles, stretching and enlarging them, forming a varicocele. Without proper blood flow, the testicles become undernourished, polluted, and overheated. This may result in infertility. Overheating is suspected to be the biggest culprit. Sperm needs to be a couple of degrees cooler than body temperature. That's why the scrotum hangs down below the body. In fact, one Japanese birth control method is simply for the man to take daily hot baths.

It is widely believed that varicoceles are the most common cause of infertility, although this is debated. 39% of males who are treated for infertility have a varicocele. Among those who have previously fathered a child but now are unable to do so, 80% have a varicocele. The good news is that fertility can be restored when the varicocele is treated.

Having a varicocele does not necessarily mean you will have fertility problems. Only 25% of men with varicoceles have a fertility problem. In fact, many men with large varicoceles have excellent sperm counts.

Often a fertility problem that appears to be caused by a varicocele turns out to be caused by something else. Varicocele surgery will result in an improvement in sperm count and motility in only about 30% of patients. The people who run infertility clinics claim that controlled trials show that the pregnancy rate does not improve after varicocele surgery and therefore you are better off spending your money at their clinic for "assisted reproductive techniques" than wasting your money on varicocele surgery. I am skeptical of their claims.

I found this gem on an infertility clinic web site: "Today, most infertility specialists would advise infertile men with varicoceles to consider going in for IVF, rather than for varicocele surgery." IVF is a service offered by infertility specialists. Varicocele surgery is not. Basically what they are saying is "We advise you to spend your money on our services rather than somewhere else."

The surgeons claim that after varicocele repair, semen quality improves in 67% of patients with the most improvement seen in sperm motility rather than in sperm count. The pregnancy rate is as high as 40% after the first year and 60% after the second year, as compared to a 10 percent pregnancy rate for uncorrected varicoceles. The average pregnancy occurs 6 to 9 months after surgery.

The improvement in sperm count following surgery may not be immediate, because it takes 3 months from the time a sperm is born to the time it is ready for action (70 days to mature and 15-20 days of transit through the ductal system). It takes a year to create a child. Three months in the sack, then 9 months in the womb. The egg that the sperm fertilizes may be ten years old at the time of fertilization.

In infertile men with low serum testosterone levels, removal of the varicocele has been shown to improve serum testosterone levels.

Several studies have shown a decrease in the testosterone levels in men with varicoceles, however it is often still within the normal range.

Varicoceles are common. About 15% of all men have a varicocele. Varicoceles usually develop slowly and there may not be any symptoms.

Varicoceles develop after puberty, most commonly in men aged 15 to 25. The sudden appearance of a varicocele in an older man may be caused by a renal tumor that affects the renal vein and impairs the blood flow through the spermatic vein. However, it is common for a varicocele to go undiagnosed until fertility problems become evident or it becomes quite enlarged, so an older man diagnosed with a varicocele may actually have had it for many years.

Varicoceles usually appear on the left side of the scrotum, but can involve both sides. Varicoceles are not a health risk and do not require treatment.

If you've been diagnosed as having a low sperm count, you should know that semen quality and quantity are not constant, and tend to vary widely over a short period of time. Therefore you should have several tests over a period of time before accepting the diagnosis as valid.