Varicocele and male infertility

Abstract

The link between varicoceles and male infertility has been a matter of debate for more than half a century. Varicocele is considered the most common correctable cause of male infertility, but some men with varicoceles are able to father children, even without intervention. In addition, improvements in semen quality after varicocelectomy do not always result in spontaneous pregnancy. Studies regarding possible pathophysiological mechanisms behind varicocele-induced infertility have tried to address these controversies. Oxidative stress seems to be a central mechanism; however, no single theory is able to explain the differential effect of varicoceles on infertility. As a consequence, careful patient selection for treatment based on couple fertility status, varicocele grade, and semen quality is critical for achieving a chance of a subsequent pregnancy. A substantial amount of data on the effects of varicocelectomy has been gathered, but inadequate study design and considerable heterogeneity of available studies mean that these data are rarely conclusive. Current evidence suggests a beneficial effect of varicocelectomy on semen quality and pregnancy outcomes in couples with documented infertility only if the male partner has a clinically palpable varicocele and affected semen parameters.

One‐carbon cycle support rescues sperm damage in experimentally induced varicocoele in rats

“…These results are consistent with previous studies showing that surgically induced varicocoele in rats can hamper spermatogenesis and sperm production [1,31,32]. In men, the impairment of spermatogenesis is proportional to the clinical grade of the varicocoele [33] and also testicular hypotrophy is evident and correlates with spermatogenetic impairment in patients with a high-grade varicocoele [34].…”

Relation of nitric oxide synthase gene (NOS3) polymorphisms to varicocele risk and post‐varicocelectomy seminal oxidative stress reduction

“…Varicoceles have been reported in about 15% of healthy males increasing to about 45% and 80% of males with primary and secondary infertility respectively (Clavijo, Carrasquillo, & Ramasamy, ). Varicocele is considered as the most common reversible cause of male infertility (Jensen et al, ).…”

Does varicocelectomy improve semen in men with azoospermia and clinically palpable varicocele?

“…One such important surgical intervention that has been studied to restore male fertility is varicocelectomy. However, the findings of the effectiveness of varicocelectomy among NOA patients are inconsistent (Abdel‐Meguid, ; Agarwal et al, ; Baazeem, Boman, Libman, Jarvi, & Zini, ; Chiba et al, ; Dubin et al, ; Esteves, Miyaoka, Roque, & Agarwal, ; Jensen et al, ; Kimura & Nagao, ; Marmar et al, ).…”

“…Varicocele may impair sperm production, resulting in abnormal semen quality ranging from oligozoospermia to complete azoospermia in 4%–14% of patients (Czaplicki, Bablok, & Janczewski, ; Damsgaard et al, ; Kadioglu et al, ; Matthews, Matthews, & Goldstein, ; Sofikitis, Miyagawa, Incze, & Andrighetti, ; Will et al, ). Pathophysiologically, theories explaining the role of varicocele in azoospermia include increased temperature, adrenal hormone and gonadotoxic metabolite refluxes, changed testicular blood flow, development of antisperm antibody, altered hypothalamic–pituitary–gonadal axis and oxidative stress (Dohle et al, ; Esteves et al, ; Hendin, Kolettis, Sharma, Thomas, & Agarwal, ; Inci & Gunay, ; Jensen et al, ; Pasqualotto, Sharma, Nelson, Thomas, & Agarwal, ; Zorgniotti & Macleod, ). These influence the sperm's physiology, reproductive potential and fertilising capacity of the haploid male gamete (Sofikitis et al, ) due to germ cell apoptosis, increased intratesticular cadmium, reduced levels of androgens (Benoff & Gilbert, ; Simsek, Türkeri, Cevik, Bircan, & Akdaş, ; Zhu et al, ) and damage of DNA and proteins in the nucleus of spermatozoa, seminiferous tubule and/or Leydig cells (Esteves et al, ; Fujisawa, Yoshida, Kojima, & Kamidono, ; Gorelick & Goldstein, ).…”