International Urology and Nephrology

, Volume 50, Issue 4, pp 583–603 | Cite as

Effect of varicocele repair on sperm DNA fragmentation: a review

  • Matheus Roque
  • Sandro C. Esteves
Urology - Review


Varicocele, the leading cause of male infertility, can impair sperm quality and fertility via various oxidative stress mechanisms. An imbalance between excessive reactive oxygen species production and antioxidant protection causes alterations in nuclear and mitochondrial sperm DNA, thus rendering a subset of varicocele men less fertile. In particular, sperm DNA fragmentation is usually elevated in men with clinical varicocele in both abnormal and normal semen parameters by the current World Health Organization criteria. In this review, we discuss the evidence concerning the association between varicocele, oxidative stress, and SDF, and the possible mechanisms involved in infertility. Furthermore, we summarize the role of varicocele repair as a means of alleviating SDF and improving fertility. Lastly, we critically appraise the evidence-based algorithm recently issued by the Society for Translational Medicine aimed at guiding urologists on the use of SDF testing in men with varicocele seeking fertility. Current evidence based on careful review of published studies confirms the effectiveness of varicocelectomy as a means of both reducing oxidatively induced sperm DNA damage and potentially improving fertility. Varicocele repair should be offered as part of treatment option for male partners of infertile couples presenting with palpable varicoceles.


Male infertility Oxidative stress Sperm DNA damage Sperm DNA fragmentation Varicocele Varicocele repair 


Authors’ contributions

MR participated in the acquisition of data, helped in data interpretation, and drafted the manuscript. SCE designed the study, helped in data interpretation and coordination, and drafted the manuscript. Both authors read and approved the final manuscript.

Compliance with ethical standards

Conflict of interest

MR has nothing to disclose. SCE is a member of the advisory panel that developed the clinical practice guidelines for sperm DNA fragmentation testing based on clinical scenarios issued by the Society for Translational Medicine (


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© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.ORIGEN, Center for Reproductive MedicineRio de JaneiroBrazil
  2. 2.ANDROFERT, Andrology and Human Reproduction ClinicCampinasBrazil
  3. 3.Division of Urology, Department of Surgery, Faculty of Medical SciencesUniversity of Campinas (UNICAMP)CampinasBrazil
  4. 4.Faculty of HealthAarhus UniversityAarhus CDenmark

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