Small Varicoceles Can Make a Big Difference in Sperm Quality

Kate Johnson

March 14, 2016

MUNICH — Even a small varicocele can significantly affect sperm quality and fertility in an otherwise healthy young man, according to a population-based study of more than 7000 army recruits in six European countries.

"This study confirms that varicocele is a common incidental finding and that there is certainly a relationship between varicocele and reduced semen quality, even in young men who are otherwise healthy and mostly asymptomatic," said lead author Ulla Nordström Joensen, MD, PhD, from Roskilde Hospital in Denmark.

"There is a significant risk of reduced semen quality even in men with the mildest grade of varicocele, which they will usually not have noticed themselves," she told Medscape Medical News.

But there is still no clear picture of what to do when a varicocele is found, she acknowledged here at the European Association of Urology 2016 Congress.

"Should they have surgery? This study did not answer that question, unfortunately," she said. However, "it's not feasible to operate on all men with varicocele and decreased semen quality. If there is a 15% incidence of varicocele and half of those men have decreased semen quality, that's too many to do surgery on."

Dr Joensen and her colleagues assessed 7067 men recruited from military review boards from 1996 to 2010 in Denmark, Estonia, Finland, Germany, Latvia, and Lithuania. Mean age of the study cohort was 19 years.

After clinical examination by a physician, 1098 of the men (16%) were diagnosed with varicocele — 518 with grade 1, 382 with grade 2, and 198 with grade 3.

A higher grade is associated with poorer semen quality, measured using World Health Organization criteria of sperm concentration, motility, and morphology.

Sperm Concentration, Motility

In fact, sperm count was significantly lower in men with grade 3 varicocele than in men without the condition (28 vs 51 million/mL; < .0005), after adjustment for cryptorchidism, time since last ejaculation, body mass index, smoking, and alcohol intake. The same pattern was seen for median rates of normal morphology (5% vs 8%; < .0005) and progressive motility (55% vs 59%; P = .031).

Even men with grade 1 varicocele have a sperm count about 20% lower than men without the condition. "Many of the men with varicocele — about 55% — had semen quality that would indicate a risk of increased time to pregnancy or even infertility," Dr Joensen reported.

In terms of reproductive hormones, varicocele was associated with higher levels of follicle-stimulating hormone and luteinizing hormone and lower levels of inhibin, "which means there is a shift toward poorer function of the Leydig cells that produce testosterone," she told Medscape Medical News.

"Whether this is something that could result in testosterone deficiency later in life we cannot answer," she explained. "If we suppose that varicocele is a progressive lesion, we don't know if their sperm concentration in 10 to 20 years would be even worse."

Testicular Function

A recent study of a nonselected population of young men from Western Australia showed that even a small varicocele can negatively affect testicular function (Hum Reprod. 2015;30:2713-2724).

That study "suggested that testicular size was smaller, sperm output was reduced, and testicular secretion of serum inhibin B was decreased," said Roger Hart, MD, professor of reproductive medicine at the University of Western Australia in Crawley, who was one of the Australian investigators.

"Consequently, the presence of varicocele is a cause of male subfertility. However, many men with varicoceles will have normal fertility, so not all men with a varicocele should be considered a candidate for surgery," he told Medscape Medical News.

Dr Joensen echoed that advice, saying that "clinicians should be aware of the relationship between varicocele and testicular function, inform the man about the risks, and discuss whether to check the man's semen quality in cases of varicocele. However, at the same time, it should be kept in mind that there are many men with varicoceles who are fertile."

Dr Joensen and Dr Hart have disclosed no relevant financial relationships.

European Association of Urology (EAU) 2016 Congress: Abstract 176. Presented March 12, 2016.


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