Sandro Esteves
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Publication
Journal: Translational Andrology and Urology
October/31/2017
Abstract
Sperm DNA fragmentation (SDF) has been generally acknowledged as a valuable tool for male fertility evaluation. While its detrimental implications on sperm function were extensively investigated, little is known about the actual indications for performing SDF analysis. This review delivers practice based recommendations on commonly encountered scenarios in the clinic. An illustrative description of the different SDF measurement techniques is presented. SDF testing is recommended in patients with clinical varicocele and borderline to normal semen parameters as it can better select varicocelectomy candidates. High SDF is also linked with recurrent spontaneous abortion (RSA) and can influence outcomes of different assisted reproductive techniques. Several studies have shown some benefit in using testicular sperm rather than ejaculated sperm in men with high SDF, oligozoospermia or recurrent in vitro fertilization (IVF) failure. Infertile men with evidence of exposure to pollutants can benefit from sperm DNA testing as it can help reinforce the importance of lifestyle modification (e.g., cessation of cigarette smoking, antioxidant therapy), predict fertility and monitor the patient's response to intervention.
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Publication
Journal: Fertility and Sterility
March/24/2016
Abstract
OBJECTIVE
To investigate the effectiveness of intracytoplasmic sperm injection (ICSI) using testicular sperm as a strategy to overcome infertility in men with high sperm DNA fragmentation (SDF).
METHODS
Prospective, observational, cohort study.
METHODS
Private IVF centers.
METHODS
A total of 147 couples undergoing IVF-ICSI and day 3 fresh ETs whose male partner has oligozoospermia and high SDF.
METHODS
Sperm injections were carried out with ejaculated sperm (EJA-ICSI) or testicular sperm (TESTI-ICSI) retrieved by either testicular sperm extraction (TESE) or testicular sperm aspiration (TESA). SDF levels were reassessed on the day of oocyte retrieval in both ejaculated and testicular specimens.
METHODS
Percentage of testicular and ejaculated spermatozoa containing fragmented DNA (%DFI) and clinical pregnancy, miscarriage, and live-birth rates.
RESULTS
The %DFI in testicular sperm was 8.3%, compared with 40.7% in ejaculated sperm. For the TESTI-ICSI group versus the EJA-ICSI group, respectively, the clinical pregnancy rate was 51.9% and 40.2%, the miscarriage rate was 10.0% and 34.3%, and the live-birth rate was 46.7% and 26.4%.
CONCLUSIONS
ICSI outcomes were significantly better in the group of men who had testicular sperm used for ICSI compared with those with ejaculated sperm. SDF was significantly lower in testicular specimens compared with ejaculated counterparts. Our results suggest that TESTI-ICSI is an effective option to overcome infertility when applied to selected men with oligozoospermia and high ejaculated SDF levels.
Publication
Journal: Fertility and Sterility
November/17/2017
Publication
Journal: Nature Reviews Urology
May/27/2013
Abstract
Varicocele is recognized as the leading cause of male infertility because it can impair spermatogenesis through several distinct pathophysiological mechanisms. Current evidence supports oxidative stress as a key element in the pathophysiology of varicocele-related infertility, although these mechanisms have not yet been fully described. Measurement of the reactive oxygen species and other markers of oxidative stress, including the levels of the antioxidant enzymes catalase and superoxide dismutase, can provide valuable information on the extent of oxidative stress and might guide therapeutic management strategies. The testis can respond to varicocele-associated cell stressors, such as heat stress, ischaemia or production of vasodilators (for example, nitric oxide) at the expense of the generation of excessive reactive oxygen species. These responses have their own implications in exacerbating the underlying oxidative stress and on the subsequent infertility.
Publication
Journal: Current Opinion in Obstetrics and Gynecology
April/26/2016
Abstract
The clinical utility of sperm DNA fragmentation tests needs to be revisited in light of increasing evidence of detrimental effect of sperm DNA damage on reproductive outcomes.
Current evidence supports the association between high sperm DNA fragmentation and poor outcomes with regards to natural conception and intrauterine insemination. The relationship between high sperm DNA fragmentation and impaired outcomes after in-vitro fertilization and intracytoplasmic sperm injection are more equivocal. However, recent studies indicate that poor sperm chromatin content is associated with an increased risk of early pregnancy loss after in-vitro fertilization and intracytoplasmic sperm injection. Several strategies are proposed to alleviate sperm DNA fragmentation and/or select sperm with higher quality chromatin content for assisted reproductive techniques. The intake of oral antioxidants, varicocele repair, use of recurrent ejaculations alone or combined with micromanipulation-based sperm selection techniques, and the use of testicular sperm for intracytoplasmic sperm injection have been attempted with promising results.
Sperm DNA fragmentation tests provide clinically relevant information for natural conception and artificial reproduction independent of those derived from conventional semen parameters. The increasing knowledge of paternal factors on pregnancy outcome and the improvement in treatment strategies should prompt routine evaluation of sperm DNA fragmentation in infertile couples.
Publication
Journal: Clinics
December/27/2011
Abstract
Male infertility is directly or indirectly responsible for 60% of cases involving reproductive-age couples with fertility-related issues. Nevertheless, the evaluation of male infertility is often underestimated or postponed. A coordinated evaluation of the infertile male using standardized procedures improves both diagnostic precision and the results of subsequent management in terms of effectiveness, risk and costs. Recent advances in assisted reproductive techniques (ART) have made it possible to identify and overcome previously untreatable causes of male infertility. To properly utilize the available techniques and improve clinical results, it is of the utmost importance that patients are adequately diagnosed and evaluated. Ideally, this initial assessment should also be affordable and accessible. We describe the main aspects of male infertility evaluation in a practical manner to provide information on the judicious use of available diagnostic tools and to better determine the etiology of the most adequate treatment for the existing condition.
Publication
Journal: Urology
February/26/2012
Abstract
In 2010, the World Health Organization established new reference values for human semen characteristics that are markedly lower than those previously reported. Despite using controlled studies involving couples with a known time to pregnancy to establish the new limits, the reference studies are limited with regard to the population analyzed and the methods used for semen evaluation. The present review discusses concerns related to the new reference values for semen characteristics, including the effect on patient referral, diagnosis, and treatment of recognized conditions, such as varicocele, and on the indications for assisted reproductive technologies.
Publication
Journal: International braz j urol : official journal of the Brazilian Society of Urology
July/7/2013
Abstract
Unexplained male infertility is a diagnosis reserved for men in whom routine semen analyses results are within normal values and physical as well as endocrine abnormalities were ruled out. In addition to erectile problems and coital factors, immunologic causes and sperm dysfunction may contribute to such condition. New etiologies of unexplained male infertility include low level leukocytospermia and mitochondrial DNA polymerase gene polymorphism. Contemporary andrology may reveal cellular and sub-cellular sperm dysfunctions which may explain subfertility in such cases, thus aiding the clinician to direct the further work-up, diagnosis and counseling of the infertile male. The objective of this article is to highlight the concept of unexplained male infertility and focuses on the diagnosis and treatment of this condition in the era of modern andrology and assisted reproductive techniques. Extensive literature review was performed using the search engines: Pubmed, Science-direct, Ovid and Scopus.
Publication
Journal: Asian Journal of Andrology
October/30/2016
Abstract
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.
Publication
Journal: European Urology
December/6/2016
Abstract
Approximately 37% of men of reproductive age smoke cigarettes, with Europe having the highest tobacco use among all the World Health Organization (WHO) regions. Toxins from tobacco smoking can potentially affect sperm development and function, with a negative effect on semen parameters. Given the high prevalence of smoking and recent changes in the WHO laboratory methods for the examination of human semen, the role of this exposure in face of new WHO methods needs to be clarified.
We conducted a systematic review, followed by a meta-analysis, to determine whether cigarette smoking affects human semen parameters. PubMed, Saint Joseph's University Discover, and Google Scholar were used to identify relevant studies published after release of the latest WHO methods for laboratory evaluation of human semen. Participants were from fertility/urologic clinics and andrology laboratories. The outcome measures were semen volume, sperm concentration, motility, and morphology, the parameters usually used in clinical settings to assess fertility.
Twenty studies with 5865 participants were included in the meta-analysis. Exposure to cigarette smoking was associated with reduced sperm count (mean difference [MD]: -9.72×106/ml; 95% confidence interval [CI], -13.32 to -6.12), motility (MD: -3.48%; 95% CI, -5.53 to -1.44), and morphology (MD: -1.37%; 95% CI, -2.63 to -0.11). Subgroup analyses indicated that effect size was higher in infertile men than in the general population and in moderate/heavy smokers than in mild smokers. The overall effect size on semen volume, sperm count, and motility remained similar when 2010 and earlier WHO manuals were used for semen analysis but was lower with regard to sperm morphology.
Our results suggest that cigarette smoking has an overall negative effect on semen parameters. The latest WHO laboratory methods for the examination of human semen had a minimal impact on the magnitude of effect size, thus confirming the observed negative effect of smoking on conventional semen parameters.
A new systematic review and meta-analysis comprising 5865 men shows that cigarette smoking is associated with reduced sperm count and motility. Deterioration of semen quality is more pronounced in moderate and heavy smokers.
Publication
Journal: Nature Reviews Urology
June/2/2013
Abstract
Varicocele, the leading cause of male infertility, can impair spermatogenesis through several pathophysiological mechanisms. Of these, current evidence suggests that oxidative stress is the central element contributing to infertility in men with varicocele, to which the testis responds by way of heat stress, ischaemia or production of vasodilators, such as nitric oxide. Surgical varicocele repair (varicocelectomy) is beneficial not only for alleviating oxidative stress-associated infertility, but also for preventing and protecting against the progressive character of varicocele and its consequent upregulations of systemic oxidative stress. However, antioxidant therapy in infertile men with surgically treated and those with untreated varicocele is poorly studied, and well-designed trials are needed.
Publication
Journal: International braz j urol : official journal of the Brazilian Society of Urology
February/26/2015
Abstract
Semen analysis is the corner stone of infertility evaluation as it provides information on the functional status of the seminiferous tubules, epididymis and accessory sex glands. The methods on how the human semen should be evaluated are provided by the World Health Organization, which periodically releases manuals that include specific protocols and reference standards. In 2010, the WHO published new criteria for human semen characteristics that were markedly lower than those previously reported. In this review initially it is discussed the limitations of semen analysis as a surrogate measure of a man's ability to father a pregnancy. Secondly, it is analyzed methodology issues that could explain why the newly released reference values were different from those earlier reported. Thirdly, it is speculated on the likely effects of the 2010 WHO criteria in the management of male infertility. Due to the several inherent limitations of semen analysis as a surrogate marker of male infertility, physicians should exercise caution when interpreting results. A template for semen analysis reports that incorporates the distribution of the semen characteristics of recent fathers in centiles rather than solely the minimum thresholds could aid clinicians to better understand how a given patient results compare with the reference population. Importantly, a male infertility evaluation must go far beyond a simple semen analysis, as it has to be complemented with a proper physical examination, a comprehensive history taking, and relevant endocrine, genetic, and other investigations.
Publication
Journal: F1000Research
September/1/2017
Abstract
In reproductive medicine little progress has been achieved regarding the clinical management of patients with a reduced ovarian reserve or poor ovarian response (POR) to stimulation with exogenous gonadotropins -a frustrating experience for clinicians as well as patients. Despite the efforts to optimize the definition of this subgroup of patients, the existing POR criteria unfortunately comprise a heterogeneous population and, importantly, do not offer any recommendations for clinical handling. Recently, the POSEIDON group ( Patient- Oriented Strategies Encompassing Individualize D Oocyte Number) proposed a new stratification of assisted reproductive technology (ART) in patients with a reduced ovarian reserve or unexpected inappropriate ovarian response to exogenous gonadotropins. In brief, four subgroups have been suggested based on quantitative and qualitative parameters, namely, i. Age and the expected aneuploidy rate; ii. Ovarian biomarkers (i.e. antral follicle count [AFC] and anti-Müllerian hormone [AMH]), and iii. Ovarian response - provided a previous stimulation cycle was performed. The new classification introduces a more nuanced picture of the "low prognosis patient" in ART, using clinically relevant criteria to guide the physician to most optimally manage this group of patients. The POSEIDON group also introduced a new measure for successful ART treatment, namely, the ability to retrieve the number of oocytes needed for the specific patient to obtain at least one euploid embryo for transfer. This feature represents a pragmatic endpoint to clinicians and enables the development of prediction models aiming to reduce the time-to-pregnancy (TTP). Consequently, the POSEIDON stratification should not be applied for retrospective analyses having live birth rate (LBR) as endpoint. Such an approach would fail as the attribution of patients to each Poseidon group is related to specific requirements and could only be made prospectively. On the other hand, any prospective approach (i.e. RCT) should be performed separately in each specific group.
Publication
Journal: Clinics
February/18/2014
Abstract
Impaired testicular function, i.e., hypogonadism, can result from a primary testicular disorder (hypergonadotropic) or occur secondary to hypothalamic-pituitary dysfunction (hypogonadotropic). Hypogonadotropic hypogonadism can be congenital or acquired. Congenital hypogonadotropic hypogonadism is divided into anosmic hypogonadotropic hypogonadism (Kallmann syndrome) and congenital normosmic isolated hypogonadotropic hypogonadism (idiopathic hypogonadotropic hypogonadism). The incidence of congenital hypogonadotropic hypogonadism is approximately 1-10:100,000 live births, and approximately 2/3 and 1/3 of cases are caused by Kallmann syndrome (KS) and idiopathic hypogonadotropic hypogonadism, respectively. Acquired hypogonadotropic hypogonadism can be caused by drugs, infiltrative or infectious pituitary lesions, hyperprolactinemia, encephalic trauma, pituitary/brain radiation, exhausting exercise, abusive alcohol or illicit drug intake, and systemic diseases such as hemochromatosis, sarcoidosis and histiocytosis X. The clinical characteristics of hypogonadotropic hypogonadism are androgen deficiency and a lack/delay/stop of pubertal sexual maturation. Low blood testosterone levels and low pituitary hormone levels confirm the hypogonadotropic hypogonadism diagnosis. A prolonged stimulated intravenous GnRH test can be useful. In Kallmann syndrome, cerebral MRI can show an anomalous morphology or even absence of the olfactory bulb. Therapy for hypogonadotropic hypogonadism depends on the patient's desire for future fertility. Hormone replacement with testosterone is the classic treatment for hypogonadism. Androgen replacement is indicated for men who already have children or have no desire to induce pregnancy, and testosterone therapy is used to reverse the symptoms and signs of hypogonadism. Conversely, GnRH or gonadotropin therapies are the best options for men wishing to have children. Hypogonadotropic hypogonadism is one of the rare conditions in which specific medical treatment can reverse infertility. When an unassisted pregnancy is not achieved, assisted reproductive techniques ranging from intrauterine insemination to in vitro fertilization to the acquisition of viable sperm from the ejaculate or directly from the testes through testicular sperm extraction or testicular microdissection can also be used, depending on the woman's potential for pregnancy and the quality and quantity of the sperm.
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Publication
Journal: International Urology and Nephrology
February/20/2015
Abstract
The diagnostic and prognostic validity of sperm function biomarkers is particularly relevant for males with unexplained infertility in which routine semen analysis fails to detect subcellular sperm dysfunctions. In this general review, we examine the role and significance of specialized andrology laboratory tests from past to present and provide a glance toward the future. We concluded that the assessment of sperm DNA damage and oxidative stress provide a relatively independent measure of fertility that yields diagnostic and prognostic information complementary to, but distinct and more significant than, standard sperm parameters. Since none of the available methods for such testing have been fully translated, further research is necessary to evaluate their cost-effectiveness when applied in large scale to daily medical practice. Application of translational medicine concepts would also be useful to accelerate the clinical application of recent discoveries in the fields of genomics, proteomics and metabolomics.
Publication
Journal: International Urology and Nephrology
May/23/2016
Abstract
OBJECTIVE
Varicocele is a frequent cause of impaired testicular function that has been associated with increased levels of sperm DNA fragmentation (SDF). Sperm with degraded DNA (DDS), as observed using the sperm chromatin dispersion (SCD) test, represent a subpopulation of spermatozoa with extensive DNA and nuclear protein damage. The aim of this work was to determine the usefulness of sperm DNA degradation index (DDSi) as a novel noninvasive biomarker to identify infertile men with varicocele.
METHODS
A total of 593 semen samples obtained from men attending infertility clinics were analyzed for SDF and DDS with the SCD test. These samples were classified as: (1) fertile donors; (2) infertile patients with least two failed assisted reproduction cycles; (3) leukocytospermia; (4) Chlamydia trachomatis infection; (5) testicular cancer, and (6) infertile men with varicocele. The DDSi was obtained by determining the proportion of DDS in the whole sperm population presenting with fragmented DNA. The diagnostic accuracy of DDSi was evaluated by correlation coefficient and receiver operating characteristics analyses.
RESULTS
A positive correlation (r ≥ 0.52) was observed between the SDF and the frequency of degraded sperm in all patient groups. The sperm DNA degradation index (DDSi) was at least twice as higher in infertile men with varicocele (mean: 0.54) compared with other clinical conditions and fertile donors (means ranging from 0.02 to 0.21; P < 0.0001). A DDSi ≥ 0.33 identified patients with varicocele with 94 % accuracy.
CONCLUSIONS
Although DDS is not pathognomonic of varicocele, the DDSi is a useful noninvasive biomaker to identify infertile individuals with varicocele when examining sperm DNA damage during a routine semen analysis. This finding may alert practitioners and laboratories performing semen analysis that in the presence of an abnormal DDSi it is likely that a given patient has varicocele. It is therefore strongly recommended that such patients be referred to urologists in order to undergo a full andrological examination and be properly counseled.
Publication
Journal: International braz j urol : official journal of the Brazilian Society of Urology
July/16/2012
Abstract
Different surgical methods such as PESA, MESA, TESA, TESE and micro-TESE have been developed to retrieve spermatozoa from either the epididymis or the testis according to the type of azoospermia, i.e., obstructive or non-obstructive. Laboratory techniques are used to remove contaminants, cellular debris, and red blood cells following collection of the epididymal fluid or testicular tissue. Surgically-retrieved spermatozoa may be used for intracytoplasmic sperm injection (ICSI) and/or cryopreservation. In this article, we review the surgical procedures for retrieving spermatozoa from both the epididymis and the testicle and provide technical details of the commonly used methods. A critical analysis of the advantages and limitations of the current surgical methods to retrieve sperm from males with obstructive and non-obstructive azoospermia is presented along with an overview of the laboratory techniques routinely used to process surgically-retrieved sperm. Lastly, we summarize the results from the current literature of sperm retrieval, as well as the clinical outcome of ICSI in the clinical scenario of obstructive and nonobstructive azoospermia.
Publication
Journal: Human Reproduction Update
November/1/2018
Abstract
BACKGROUND
Elective freezing of all good quality embryos and transfer in subsequent cycles, i.e. elective frozen embryo transfer (eFET), has recently increased significantly with the introduction of the GnRH agonist trigger protocol and improvements in cryo-techniques. The ongoing discussion focuses on whether eFET should be offered to the overall IVF population or only to specific subsets of patients. Until recently, the clinical usage of eFET was supported by only a few randomized controlled trials (RCT) and meta-analyses, suggesting that the eFET not only reduced ovarian hyperstimulation syndrome (OHSS), but also improved reproductive outcomes. However, the evidence is not unequivocal, and recent RCTs challenge the use of eFET for the general IVF population.
UNASSIGNED
This systematic review and meta-analysis aimed at evaluating whether eFET is advantageous for reproductive, obstetric and perinatal outcomes compared with fresh embryo transfer in IVF/ICSI cycles. Additionally, we evaluated the effectiveness of eFET in comparison to fresh embryo transfer in different subgroups of patients undergoing IVF/ICSI cycles.
METHODS
We conducted a systematic review, using PubMed/Medline and EMBASE to identify all relevant RCTs published until March 2018. The participants included infertile couples undergoing IVF/ICSI with or without preimplantation genetic testing for aneuploidy (PGT-A). The primary outcome was the live birth rate (LBR), whereas secondary outcomes were cumulative LBR, implantation rate, miscarriage, OHSS, ectopic pregnancy, preterm birth, pregnancy-induced hypertension, pre-eclampsia, mean birthweight and congenital anomalies. Subgroup analyses included normal and hyper-responder patients, embryo developmental stage on the day of embryo transfer, freezing method and the route of progesterone administration for luteal phase support in eFET cycles.
RESULTS
Eleven studies, including 5379 patients, fulfilling the inclusion criteria were subjected to qualitative and quantitative analysis. A significant increase in LBR was noted with eFET compared with fresh embryo transfer in the overall IVF/ICSI population [risk ratio (RR) = 1.12; 95% CI: 1.01-1.24]. Subgroup analyses indicated higher LBRs by eFET than by fresh embryo transfer in hyper-responders (RR = 1.16; 95% CI: 1.05-1.28) and in PGT-A cycles (RR = 1.55; 95% CI: 1.14-2.10). However, no differences were observed for LBR in normo-responders (RR = 1.03; 95% CI: 0.91-1.17); moreover, the cumulative LBR was not significantly different in the overall population (RR = 1.04; 95% CI: 0.97-1.11). Regarding safety, the risk of moderate/severe OHSS was significantly lower with eFET than with fresh embryo transfer (RR = 0.42; 95% CI: 0.19-0.96). In contrast, the risk of pre-eclampsia increased with eFET (RR = 1.79; 95% CI: 1.03-3.09). No statistical differences were noted in the remaining secondary outcomes.
UNASSIGNED
Although the use of eFET has steadily increased in recent years, a significant increase in LBR with eFET was solely noted in hyper-responders and in patients undergoing PGT-A. Concerning safety, eFET significantly decreases the risk of moderate and severe OHSS, albeit at the expense of an increased risk of pre-eclampsia.
Publication
Journal: Fertility and Sterility
February/23/2014
Abstract
OBJECTIVE
To compare the sperm chromatin dispersion (SCD) test and the terminal uridine nick-end labeling (TUNEL) assay for assessment of sperm DNA damage.
METHODS
Prospective comparative experimental study.
METHODS
Andrology laboratory.
METHODS
Twenty subfertile men with unexplained infertility.
METHODS
Sperm DNA damage was determined in the same semen samples using the TUNEL assay with fluorescence microscopy and the SCD test with bright-field microscopy.
METHODS
Correlation coefficient and receiver operating characteristic analysis outcomes. The TUNEL assay was used as the reference standard to identify optimal cutoff points for assessing DNA damage by SCD.
RESULTS
The SCD test detected a significantly higher proportion of sperm with damaged DNA (20.6% ± 14.0%) than the TUNEL assay (11.5% ± 7.3%). Spearman's rank correlation showed that the methods were not comparable (r = 0.29). Receiver operating characteristic analysis revealed that 15% was the best SCD cutoff point to classify patients within the same levels of DNA fragmentation, normal or abnormal, as determined by the TUNEL assay, with an accuracy of 69%.
CONCLUSIONS
The SCD test is more sensitive than the TUNEL assay for the assessment of DNA damage in men with unexplained infertility. Although the methods are poorly correlated, SCD may discriminate men with normal and abnormal sperm DNA damage with moderate accuracy when compared with TUNEL. It is important to distinguish between the methods because they differently evaluate sperm DNA damage.
Publication
Journal: Frontiers in Endocrinology
November/13/2018
Abstract
Hypo-responsiveness to controlled ovarian stimulation is an undervalued topic in reproductive medicine. This phenomenon manifests as a low follicles output rate (FORT) with a discrepancy between the relatively low number of pre-ovulatory follicles which develop following ovarian stimulation as compared to the number of antral follicles available at the start of stimulation. The pathophysiology mechanisms explaining the ovarian resistance to gonadotropin stimulation are not fully understood, but the fact that both hypo-responders and normal responders share similar phenotypic characteristics suggests a genotype-based mechanism. Indeed, existing evidence supports the association between specific gonadotropin and their receptor polymorphisms and ovarian hypo-response. Apart from genotypic trait, environmental contaminants and oxidative stress might also be involved in the hypo-response pathogenesis. The ratio between the number of oocytes collected at the ovum pick up and the number of antral follicles at the beginning of OS [Follicle to oocyte index (FOI)] is proposed as a novel parameter to assess the hypo-response. Compared with traditional ovarian reserve markers, FOI might reflect most optimally the dynamic nature of follicular growth in response to exogenous gonadotropin. In this review, we contextualize the role of FOI as a parameter to identify this condition, discuss the underlying mechanisms potentially implicated in the pathogenesis of hypo-response, and appraise possible the treatment strategies to overcome hyper-responsiveness to gonadotropin stimulation.
Publication
Journal: Asian Journal of Andrology
October/30/2016
Abstract
Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist's profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocele that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact.
Publication
Journal: Clinics
February/18/2014
Abstract
Azoospermia due to obstructive and non-obstructive mechanisms is a common manifestation of male infertility accounting for 10-15% of such cases. Known genetic factors are responsible for approximately 1/3 of cases of azoospermia. Nonetheless, at least 40% of cases are currently categorized as idiopathic and may be linked to unknown genetic abnormalities. It is recommended that various genetic screening tests are performed in azoospermic men, given that their results may play vital role in not only identifying the etiology but also in preventing the iatrogenic transmission of genetic defects to offspring via advanced assisted conception techniques. In the present review, we examine the current genetic information associated with azoospermia based on results from search engines, such as PUBMED, OVID, SCIENCE DIRECT and SCOPUS. We also present a critical appraisal of use of genetic testing in this subset of infertile patients.
Publication
Journal: International braz j urol : official journal of the Brazilian Society of Urology
June/14/2006
Abstract
OBJECTIVE
Analyze whether testicular histologic patterns from a group of azoospermic men with varicocele is predictive of treatment outcome after subinguinal microsurgical varicocele repair.
METHODS
Seventeen azoospermic men underwent bilateral open single testis biopsy and microsurgical subinguinal repair of clinical varicoceles.
RESULTS
Histopathology of testicular biopsies revealed hypospermatogenesis (HYPO) in 6 men, maturation arrest (MA) in 5, and Sertoli cell-only (SCO) in 6. Overall, presence of spermatozoa in the ejaculates was achieved in 47% (8/17) of men after varicocele repair, but only 35% (6/17) of them had motile sperm in their ejaculates. Only men with testicular histology revealing HYPO (5/6) or maturation arrest (3/5) had improvement after surgery. Median (25%-75% percentile) postoperative motile sperm count for both groups were 0.9 x 10(6)/mL (0.1-1.8 x 10(6)/mL) and 0.7 x 10(6)/mL (0.1-1.1), respectively (p = 0.87). The mean time for appearance of spermatozoa in the ejaculates was 5 months (3 to 9 months). One (HYPO) of 8 (12.5%) men who improved after surgery contributed to an unassisted pregnancy. Postoperative testicular biopsies obtained from patients who had no improvement after surgery revealed that testicular histology diagnosis remained unchanged. Successful testicular sperm retrieval for intracytoplasmic sperm injection (ICSI) was achieved in 4 of 9 (44.4%) individuals who did not improve after surgery, including 1 man with testicular histology exhibiting SCO.
CONCLUSIONS
Microsurgical varicocele repair in nonobstructive azoospermic men with clinical varicoceles can result in sperm appearance in the ejaculate when hypospermatogenesis or maturation arrest is found on testicular histology diagnosis.
Publication
Journal: Environmental International
September/24/2014
Abstract
Mobile phones are owned by most of the adult population worldwide. Radio-frequency electromagnetic radiation (RF-EMR) from these devices could potentially affect sperm development and function. Around 14% of couples in high- and middle-income countries have difficulty conceiving, and there are unexplained declines in semen quality reported in several countries. Given the ubiquity of mobile phone use, the potential role of this environmental exposure needs to be clarified. A systematic review was therefore conducted, followed by meta-analysis using random effects models, to determine whether exposure to RF-EMR emitted from mobile phones affects human sperm quality. Participants were from fertility clinic and research centres. The sperm quality outcome measures were motility, viability and concentration, which are the parameters most frequently used in clinical settings to assess fertility. We used ten studies in the meta-analysis, including 1492 samples. Exposure to mobile phones was associated with reduced sperm motility (mean difference -8.1% (95% CI -13.1, -3.2)) and viability (mean difference -9.1% (95% CI -18.4, 0.2)), but the effects on concentration were more equivocal. The results were consistent across experimental in vitro and observational in vivo studies. We conclude that pooled results from in vitro and in vivo studies suggest that mobile phone exposure negatively affects sperm quality. Further study is required to determine the full clinical implications for both sub-fertile men and the general population.
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