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Introduction
Current institution
Publications
Publications (276)
Purpose:
Surgical sperm retrieval (SSR) is used to extract spermatozoa for use with intracytoplasmic sperm injection in men with obstructive and non-obstructive azoospermia (NOA). The procedure may lead to segmental devascularization, postoperative fibrosis, and atrophy with a subsequent decrease in testosterone. The aim of the study is to investi...
Sperm DNA fragmentation (SDF) has been associated with male infertility, recurrent pregnancy loss, and failure of assisted reproductive technologies. Pathogenesis of SDF involves both intrinsic and extrinsic factors, causing protamine deficiency, abortive apoptosis, and oxidative stress. In the latest edition of the WHO laboratory manual for the ex...
Purpose: This study aimed to examine current global practices in regenerative therapy (RT) for erectile dysfunction (ED) and to establish expert recommendations for its use, addressing the current lack of solid evidence and standardized guidelines.Materials and Methods: Materials and Methods: A 39-question survey was developed by senior Global Andr...
Purpose:
Varicoceles can be a source of elevated seminal oxidative stress (OS) and sperm DNA fragmentation (SDF). However, it remains unclear whether varicocele repair (VR) could reduce these parameters. This systematic review and meta-analysis (SRMA) aims to investigate the impact of VR on SDF and seminal malondialdehyde (MDA).
Materials and met...
Purpose:
Sperm DNA fragmentation (SDF) is a functional sperm abnormality that can impact reproductive potential, for which four assays have been described in the recently published sixth edition of the WHO laboratory manual for the examination and processing of human semen. The purpose of this study was to examine the global practices related to t...
Purpose
Sperm DNA fragmentation (SDF) testing was recently added to the sixth edition of the World Health Organization laboratory manual for the examination and processing of human semen. Many conditions and risk factors have been associated with elevated SDF; therefore, it is important to identify the population of infertile men who might benefit...
Study question
What is the impact of advanced paternal age (APA) on sperm DNA fragmentation index (DFI)?
Summary answer
Sperm DFI levels remain relatively stable until the age of 35 and increase progressively beyond that age.
What is known already
APA can have a negative impact on male fertility and the health of offspring. Previous studies have...
Purpose:
The purpose of this meta-analysis is to study the impact of varicocele repair in the largest cohort of infertile males with clinical varicocele by including all available studies, with no language restrictions, comparing intra-person conventional semen parameters before and after the repair of varicoceles.
Materials and methods:
The met...
Purpose
Varicocele is a common problem among infertile men. Varicocele repair (VR) is frequently performed to improve semen parameters and the chances of pregnancy. However, there is a lack of consensus about the diagnosis, indications for VR and its outcomes. The aim of this study was to explore global practice patterns on the management of varico...
Purpose: Despite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on
conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated
the impact of VR on sperm concentration, total motility, and progressive motility, mostly usi...
Biomedical science is rapidly developing in terms of more transparency, openness and reproducibility of scientific publications. This is even more important for all studies that are based on results from basic semen examination. Recently two concordant documents have been published: the 6th edition of the WHO Laboratory Manual for the Examination a...
Purpose:
Seminal oxidative stress (OS) is a recognized factor potentially associated with male infertility, but the efficacy of antioxidant (AOX) therapy is controversial and there is no consensus on its utility. Primary outcomes of this study were to investigate the effect of AOX on spontaneous clinical pregnancy, live birth and miscarriage rates...
We would like to thank F. Pallotti and his colleagues for their positive comments [...].
Antisperm antibodies (ASA), as a cause of male infertility, have been detected in infertile males as early as 1954. Multiple causes of ASA production have been identified, and they are due to an abnormal exposure of mature germ cells to the immune system. ASA testing (with mixed anti-globulin reaction, and immunobead binding test) was described in...
Study question
Does advancing paternal age correlate with sperm DNA fragmentation index (DFI) and is there a cut-off age beyond which sperm DFI increases significantly?
Summary answer
In infertile men, DFI correlate with advancing paternal age and should be routinely screened starting 35 years of age.
What is known already
In recent decades, birt...
The inability to conceive due to male infertility is a complex issue with a wide variety of etiologies. Sperm DNA damage can be both a barrier to natural pregnancy and successful assisted reproductive technology (ART). The aim of this narrative review was to describe and highlight the effects of sperm DNA fragmentation and the most recent data on v...
Sperm vitality testing is a basic semen examination that has been described in the World Health Organization (WHO) Laboratory
Manual for the Examination and Processing of Human Semen from its primary edition, 40 years ago. Several methods can be used to test sperm vitality, such as the eosin-nigrosin (E-N) stain or the hypoosmotic swelling (HOS) te...
Testicular sperm retrieval (TSR) techniques are valuable in the context of severe idiopathic male factor infertility; however, there are few studies in the literature examining the long‐term impact of TSR on testicular function. The objective was to determine whether testicular sperm aspiration (TESA) or microdissection testicular sperm extraction...
Purpose: The success of vasectomy is determined by the outcome of a post-vasectomy semen analysis (PVSA). This article describes a step-by-step procedure to perform PVSA accurately, report data from patients who underwent post vasectomy semen analysis between 2015 and 2021 experience, along with results from an international online survey on clinic...
Semen analysis is the cornerstone of male fertility evaluation with WHO guidelines providing the basis for procedural standardization and reference values worldwide. The first WHO manual was published in 1980, and five editions have been subsequently released over the last four decades. The 6th Edition was published in July 2021. In this review, we...
One of modern healthcare's most controversial areas, reproductive medicine is an emerging discipline that fosters hugely divergent opinions on topics such as laboratory techniques, clinical management and ethical considerations. Highlighting over 50 contentious topics in reproductive medicine, this book presents expertly argued opinions are present...
Objectives
Men with nonobstructive azoospermia (NOA), cryptozoospermia and severe oligozoospermia are candidates for microdissection testicular sperm extraction (micro-TESE) and intracytoplasmic sperm injection (ICSI). We sought to evaluate micro-TESE outcomes and the need for bilateral testicular exploration in the three groups of men.
Methods
We...
While most men with non-obstructive azoospermia (NOA) are not amenable to medical treatment, some men can be treated effectively with hormonal therapy, prior to considering surgery. In some cases, hormonal therapy alone can treat NOA, without the need for surgery. In other cases, correction of a potential hormonal imbalance can enhance the chances...
Purpose:
The use of antioxidants is common practice in the management of infertile patients. However, there are no established guidelines by professional societies on antioxidant use for male infertility.
Materials and methods:
Using an online survey, this study aimed to evaluate the practice pattern of reproductive specialists to determine the...
Semen analysis is the first, and frequently, the only step in the evaluation of male fertility. Although the laboratory procedures are conducted according to the World Health Organization (WHO) guidelines, semen analysis and especially sperm morphology assessment is very difficult to standardize and obtain reproducible results. This is mainly due t...
The current WHO 2010 manual for human semen analysis defines leukocytospermia as the presence of peroxidase-positive
leukocytes at a concentration >1×106/mL of semen. Granular leukocytes when activated are capable of generating high levels
of reactive oxygen species in semen resulting in oxidative stress. Oxidative stress has been correlated with p...
This chapter includes clinical cases, background, evidence‐based practical management options, preventive measures, key‐point summaries of sperm retrieval in cancerous testes important details and answers to questions patients ask. Testicular cancer is the most common malignancy among men between 14 and 44 years of age, affecting them during the pe...
Retrograde ejaculation (RE) is a condition defined as the backward flow of the semen during ejaculation, and when present
can result in male infertility. RE may be partial or complete, resulting in either low seminal volume or complete absence of
the ejaculate (dry ejaculate). RE can result from anatomic, neurological or pharmacological conditions....
Objectives
To evaluate and compare sperm retrieval outcomes by testicular sperm aspiration (TESA) and micro-dissection testicular sperm extraction (micro-TESE) in non-azoospermic men.
Methods
We conducted a retrospective study of 145 consecutive testicular sperm retrievals in men with cryptozoospermia (n=56) or severe oligozoospermia (n=84). The d...
Sperm DNA fragmentation (SDF) is implicated in male infertility and adverse reproductive outcomes. With the publication of
many studies regarding the etiologies and contributors to SDF, as well as the effects of SDF, guidelines are necessary to aid
clinicians in the application of SDF for male fertility evaluation. Two recent clinical practice guid...
The prolonged lockdown of health facilities providing non‐urgent gamete cryopreservation –as currently recommended by many reproductive medicine entities and regulatory authorities due to the SARS‐CoV‐2 pandemic will be detrimental for subgroups of male infertility patients. We believe the existing recommendations should be promptly modified and pr...
Introduction:
Several studies addressed the role of testicular sperm aspiration with intracytoplasmic sperm injection (ICSI) in azoospermic men but few have included non- azoospermic men. The aim of this study was to evaluate testicular sperm aspiration (TESA) sperm retrieval rates and ICSI outcomes in men with severe oligozoospermia.
Methods:
D...
Introduction
Micro‐dissection testicular sperm extraction (micro‐TESE) is a procedure commonly utilized to harvest spermatozoa in severe male factor infertility. We have developed a technique involving a mini tunica albuginea incision with superficial tissue dissection (mini‐incision micro‐TESE). The modification is designed to reduce potential tis...
The rationale for using antioxidants during in vitro sperm processing stems from the inherent capacity of human spermatozoa to generate reactive oxygen species (oxidants) and from the susceptibility of these cells to oxidative stress. During semen processing, spermatozoa are particularly vulnerable to oxidative stress because the antioxidant-rich s...
Sperm DNA fragmentation (SDF) has been linked with male infertility, and previous studies suggest that SDF can have negative influence on pregnancy outcomes with assisted reproduction. We performed a retrospective review of consecutive couples with a high SDF level that had intracytoplasmic sperm injection (ICSI) using testicular sperm (T-ICSI). We...
Subclinical varicocele is an abnormality of testicular blood flow characterized by instrumentally measurable venous reflux detected by a variety of diagnostic tools in the absence of clinically detectable varicocele. It has been suggested that subclinical varicocele in children is a risk factor for the progression to a clinically detectable varicoc...
Varicocele is a common problem in infertility practice. Varicocele is encountered in 15% of healthy men and up to 35% of men with primary infertility. In this chapter, we have identified the prevalence of varicocele among different populations. We also highlighted the importance of some associated conditions, such as venous insufficiency and body m...
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen
characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose
and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in...
Background:
The sperm DNA methylation landscape is unique and critical for offspring health. If gamete-derived DNA methylation escapes reprograming in early embryos, epigenetic defects in sperm may be transmitted to the next generation. Current techniques to assess sperm DNA methylation show bias toward CpG-dense regions and do not target areas of...
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diag- nose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role...
Sperm DNA fragmentation has been associated with abnormal semen parameters and poor reproductive outcomes. To overcome the effect of sperm DNA damage on reproduction, several investigators advocate the use of testicular rather than ejaculated sperm for intracytoplasmic sperm injection (ICSI). In men with cryptozoospermia (variant of nonobstructive...
Objective:
To determine the magnitude of improvement in semen parameters after a varicocelectomy and the fraction that have improvements such that couples needing IVF or IUI are "upgraded" to needing less invasive assisted reproductive technology (ART).
Design:
Retrospective review of prospectively collected data.
Setting:
Academic medical cen...
We demonstrate a rapid, sensitive, and low cost paper-based approach for sperm chromatin integrity analysis that quantifies both DNA fragmentation and packaging. The paper-based test provides identical clinical outcome as the gold standard sperm chromatin structure assay. This technology is fast, simple, and suitable for broad application in clinic...
p>Vasectomy is a safe and effective method of birth control. Although it is a simple elective procedure, vasectomy is associated with potential minor and major complications. The early failure rate of vasectomy (presence of motile sperm in the ejaculate at 3‒6 months post-vasectomy) is in the range of 0.3‒9% and the late failure rate is in the rang...
There is evidence to show that varicocele repair can improve conventional sperm parameters but the effects on sperm chromatin integrity have not been fully elucidated. We sought to examine the effects of varicocelectomy on sperm maturation, nuclear chromatin integrity and nuclear sulfhydryl groups. We conducted a prospective study of consecutive in...
Sperm DNA damage is prevalent among infertile men and is known to influence natural reproduction. However, the impact of sperm DNA damage on assisted reproduction outcomes remains controversial. Here, we conducted a meta-analysis of studies on sperm DNA damage (assessed by SCSA, TUNEL, SCD, or Comet assay) and clinical pregnancy after IVF and/or IC...
We present a passive microfluidic sperm selection strategy that collects motile sperm based on their preference to follow boundaries and turn corners. Clinical assessment of selected human sperm from the device revealed a strong correlation between high DNA integrity and the tendency for sperm to follow boundaries. Human sperm with preference to fo...
Background:
More than 70 million couples worldwide are affected by infertility, with male-factor infertility accounting for about half of the cases. Semen analysis is critical for determining male fertility potential, but conventional testing is costly and complex. Here, we demonstrate a paper-based microfluidic approach to quantify male fertility...
Microdissection testicular sperm extraction (micro-TESE) was developed to minimize the testicular injury associated with multiple open TESEs. We sought to evaluate a mini-incision micro-TESE in men with cryptozoospermia and non-obstructive azoospermia (NOA). We conducted a retrospective study of 26 consecutive men with NOA and cryptozoospermia who...
DNA analysis is essential for diagnosis and monitoring of many diseases. Conventional DNA testing is generally limited to the laboratory. Increasing access to relevant technologies can improve patient care and outcomes in both developed and developing regions. Here, we demonstrate direct DNA analysis in paper-based devices, uniquely enabled by ion...
Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodelled during spermatogenesis. While high dose folic acid supplementation (up to ten times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementat...
Semen analysis is the most important and most widely used test of male fertility potential. In 2010, the World Health Organization (WHO) released new reference values based on the semen analysis results from prospective studies of recent fathers and healthy men from the general population. Although these new cutoff or threshold levels are now evide...
Selection medium is important in sperm isolation for assisted reproductive technologies. Contrary to the naturally occurring human cervical mucus which has a high viscosity, most current practices for motility based sperm selection use a low viscosity medium. In this study, we used a microfluidic device to assess the effects of high viscosity media...
The minimum sperm count and quality that must be identified during microdissection testicular sperm extraction (micro-TESE) to deem the procedure successful remains to be established. We conducted a retrospective study of 81 consecutive men with non-obstructive azoospermia who underwent a primary (first) micro-TESE between March 2007 and October 20...
INTRODUCTION AND OBJECTIVES: Literature on post va-sectomy pain rates and complications is disparate. Also, sterility implications of the updated AUA Guidelines on post vasectomy semen analysis is not yet known. METHODS: Four year, single surgeon (TSK) retrospective review of office vasectomies. Surgical and demographic data, semen analyses (SA), a...
Several studies support of the use of testicular rather than ejaculated spermatozoa for intracytoplasmic sperm injection (ICSI) in couples with virtual azoospermia or cryptozoospermia, although this approach remains controversial. We sought to evaluate sperm retrieval outcomes with microdissection testicular sperm extraction (micro-TESE) in men wit...
Subfertile men and women are usually cared for by different clinicians, namely urologists and gynaecologists. While these doctors share each other's goals, they may not always appreciate the content or implications of their opposite number's clinical decisions; to some degree they may practice in "silos." We address this problem by reviewing the ef...
Sperm DNA methylation abnormalities have been detected in oligozoospermic men. However, the association between sperm DNA methylation defects, sperm parameters and sperm DNA, and chromatin integrity remains poorly understood. This study was designed to clarify this issue. We recruited a cohort of 92 men (62 normozoospermic and 30 oligoasthenozoospe...
Varicocele is a common problem in reproductive medicine practice. A varicocele is identified in 15% of healthy men and up to 35% of men with primary infertility. The exact pathophysiology of varicoceles is not very well understood, especially regarding its effect on male infertility. We have conducted a systematic review of studies evaluating the e...
Objective
To investigate the association between seminal hyperviscosity, the extent of semenogelin degradation, and sperm DNA integrity (DNA fragmentation index [DFI] and high DNA stainability [HDS]) in semen from infertile couples.
Design
Prospective study.
Setting
University-affiliated fertility center.
Patient(s)
Twenty-four consecutive infer...
To formulate nomograms based on pre-repair characteristics to predict improvements in semen parameters after varicocele repair.
Model using multivariable linear regression based on prospectively collected database, with performance was quantified by concordance correlation coefficient and Pearson correlation coefficient after internal validation wi...
Infertile men have higher levels of semen reactive oxygen species (ROS) than do fertile men. High levels of semen ROS can cause sperm dysfunction, sperm DNA damage, and reduced male reproductive potential. These observations suggest that oxidative stress (OS) is an important cause of male infertility. This has led clinicians to treat infertile men...
Objective
To report a case of an infertile man with nonobstructive azoospermia who underwent simultaneous radical orchiectomy for testicular cancer and testicular sperm extraction (TESE) for preservation of fertility.
Design
Case report and literature review.
Setting
University teaching hospital.
Patient(s)
A couple being treated for infertility...
To evaluate sperm DNA fragmentation in normozoospermic male partners of couples undergoing infertility evaluation.
Retrospective cohort study.
Clinical andrology laboratory.
A total of 1,974 consecutive normozoospermic men selected from a larger cohort of 4,345 consecutive, nonazoospermic men presenting for infertility evaluation.
None.
Clinical pa...
Sperm DNA damage is common in infertile men and is associated with poor semen parameters but the impact of an isolated sperm abnormality on sperm DNA damage has not been studied.
To evaluate sperm DNA damage in a large cohort of infertile men with isolated sperm defects.
Retrospective study of 1084 consecutive, non-azoospermic infertile men with an...
Over the past 20 years, numerous new methods have been developed to identify changes in the organization and composition of sperm chromatin as well as to determine the extent of DNA damage in the nuclei of spermatozoa. Although these methods are being used effectively in assessing how toxicants act on sperm chromatin quality in agricultural setting...
Sperm selection is essential to assisted reproductive technology (ART), influencing treatment outcomes and the health of offspring. The fundamental challenge of sperm selection is dictated by biology: a heterogeneous population of ~10(8) sperm per milliliter with a short lifetime in vitro. However, conventional sperm selection approaches result in...