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Campinas, Brazil

Cho C.-L.,Kwong Wah Hospital | Esteves S.C.,Center for Male Reproduction | Agarwal A.,American Center for Reproductive Medicine
Asian Journal of Andrology | Year: 2016

Varicocele has been associated with reduced male reproductive potential. With the advances in biomolecular techniques, it has been possible to better understand the mechanisms involved in testicular damage provoked by varicocele. Current evidence suggests the central role of reactive oxygen species (ROS) and the resultant oxidative stress (OS) in the pathogenesis of varicocele-associated male subfertility although the mechanisms have not yet been fully described and it is likely to be multifactorial. Excessive ROS is associated with sperm DNA fragmentation, which may mediate the clinical manifestation of poor sperm function and fertilization outcome related to varicocele. Testing of ROS/OS and DNA fragmentation has the potential to provide additional diagnostic and prognostic information compared to conventional semen analysis and may guide therapeutic management strategies in individual patient. © 2016 AJA, SIMM & SJTU. Source


Roque M.,Center for Reproductive Medicine | Esteves S.C.,Center for Male Reproduction
Asian Journal of Andrology | Year: 2016

A systematic review was conducted to identify and qualitatively analyze the methods as well as recommendations of Clinical Practice Guidelines (CPG) and Best Practice Statements (BPS) concerning varicocele in the pediatric and adolescent population. An electronic search was performed with the MEDLINE, EMBASE, Science Direct, and Scielo databases, as well as guidelines′ Web sites until September 2015. Four guidelines were included in the qualitative synthesis. In general, the recommendations provided by the CPG/BPS were consistent despite the existence of some gaps across the studies. The guidelines issued by the American Urological Association (AUA) and American Society for Reproductive Medicine (ASRM) did not provide evidence-based levels for the recommendations given. Most of the recommendations given by the European Association of Urology (EAU) and European Society of Pediatric Urology (ESPU) were derived from nonrandomized clinical trials, retrospective studies, and expert opinion. Among all CPG/BPS, only one was specifically designed for the pediatric population. The studied guidelines did not undertake independent cost-effectiveness and risk-benefit analysis. The main objectives of these guidelines were to translate the best evidence into practice and provide a framework of standardized care while maintaining clinical autonomy and physician judgment. However, the limitations identified in the CPG/BPS for the diagnosis and management of varicocele in children and adolescents indicate ample opportunities for research and future incorporation of higher quality standards in patient care. © 2016 AJA, SIMM & SJTU. Source


Esteves S.C.,Center for Male Reproduction | Roque M.,Center for Reproductive Medicine | Agarwal A.,American Center for Reproductive Medicine
Asian Journal of Andrology | Year: 2016

Varicocele affects approximately 35%-40% of men presenting for an infertility evaluation. There is fair evidence indicating that surgical repair of clinical varicocele improves semen parameters, decreases seminal oxidative stress and sperm DNA fragmentation, and increases the chances of natural conception. However, it is unclear whether performing varicocelectomy in men with clinical varicocele prior to assisted reproductive technology (ART) improve treatment outcomes. The objective of this study was to evaluate the role of varicocelectomy on ART pregnancy outcomes in nonazoospermic infertile men with clinical varicocele. An electronic search was performed to collect all evidence that fitted our eligibility criteria using the MEDLINE and EMBASE databases until April 2015. Four retrospective studies were included, all of which involved intracytoplasmic sperm injection (ICSI), and accounted for 870 cycles (438 subjected to ICSI with prior varicocelectomy, and 432 without prior varicocelectomy). There was a significant increase in the clinical pregnancy rates (OR = 1.59, 95% CI: 1.19-2.12, I2 = 25%) and live birth rates (OR = 2.17, 95% CI: 1.55-3.06, I2 = 0%) in the varicocelectomy group compared to the group subjected to ICSI without previous varicocelectomy. Our results indicate that performing varicocelectomy in patients with clinical varicocele prior to ICSI is associated with improved pregnancy outcomes. © 2016 AJA, SIMM & SJTU. Source


Esteves S.C.,Center for Male Reproduction | Varghese A.C.,Montreal Reproductive Center
Journal of Human Reproductive Sciences | Year: 2012

Spermatozoa from azoospermic males can be retrieved from either the epididymis or the testis, depending on the type of azoospermia, using different surgical methods such as percutaneous epididymal sperm aspiration (PESA), testicular sperm aspiration (TESA), testicular sperm extraction (TESE), and microsurgical testicular sperm extraction (micro-TESE). After collecting the epididymal fluid or testicular tissue, laboratory techniques are used to remove contaminants, cellular debris, noxious microorganisms, and red blood cells. Processed spermatozoa may be used for intracytoplasmic sperm injection or eventually be cryopreserved. However, spermatozoa collected from either the epididymis or the testis are often compromised and more fragile than ejaculated ones. Therefore, sperm processing techniques should be used with great caution to avoid jeopardizing the sperm fertilizing potential in treatment cycles. In this review, we describe the current methods for processing surgically-retrieved specimens, either fresh or frozen-thawed, and provide the tips and pitfalls for facilitating the handling of such specimens. In addition, we present the available laboratory tools to aid in the identification of viable immotile spermatozoa to be used in conjunction with assisted reproductive techniques. Review of the literature was carried out using PubMed and Science Direct search engines. Source


Esteves S.C.,Center for Male Reproduction | Agarwal A.,Cleveland Clinic
International Braz J Urol | Year: 2011

Extraordinary advances have been achieved in the field of male infertility in the last decades. There are new concepts in sperm physiology and several modern tools for the assessment of spermatogenesis kinetics in vivo. New tests using molecular biology and DNA damage assays allow the clinician to correctly diagnose men so far classified as having idiopathic male infertility. In the field of treatment, microsurgery has increased success rates either for reconstruction of the reproductive tract or the retrieval of spermatozoa for assisted conception. Emerging evidence suggests that life-style and environmental conditions are of utmost importance in male fertility and subfertility. This review discusses several concepts that have changed over the last years, such as the duration of the spermatogenic cycle in humans, Y-chromosome infertility, the reproductive potential of non-mosaic Klinefelter syndrome men, the impact of paternal age and sperm DNA in male infertility, the role of antioxidants in the treatment of infertile men, the predictive factors and techniques for sperm retrieval in non-obstructive azoospermia, and the microsurgical treatment of clinical varicoceles. Whenever possible, levels of evidence are provided as suggested by the Oxford Center of Evidence-based Medicine. Source

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