Technical Aspects and Clinical Limitations of Sperm DNA Fragmentation Testing in Male Infertility: A Global Survey, Current Guidelines, and Expert Recommendations.

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 the use of SDF assays and investigate the barriers and limitations that clinicians face in incorporating these tests into their practice. MATERIALS AND METHODS: Clinicians managing male infertility were invited to complete an online survey on practices related to SDF diagnostic and treatment approaches. Their responses related to the technical aspects of SDF testing, current professional society guidelines, and the literature were used to generate expert recommendations via the Delphi method. Finally, challenges related to SDF that the clinicians encounter in their daily practice were captured. RESULTS: The survey was completed by 436 reproductive clinicians. Overall, terminal deoxynucleotidyl transferase deoxyuridine triphosphate Nick-End Labeling (TUNEL) is the most commonly used assay chosen by 28.6%, followed by the sperm chromatin structure assay (24.1%), and the sperm chromatin dispersion (19.1%). The choice of the assay was largely influenced by availability (70% of respondents). A threshold of 30% was the most selected cut-off value for elevated SDF by 33.7% of clinicians. Of respondents, 53.6% recommend SDF testing after 3 to 5 days of abstinence. Although 75.3% believe SDF testing can provide an explanation for many unknown causes of infertility, the main limiting factors selected by respondents are a lack of professional society guideline recommendations (62.7%) and an absence of globally accepted references for SDF interpretation (50.3%). CONCLUSIONS: This study represents the largest global survey on the technical aspects of SDF testing as well as the barriers encountered by clinicians. Unified global recommendations regarding clinician implementation and standard laboratory interpretation of SDF testing are crucial.

Controversy and Consensus on Indications for Sperm DNA Fragmentation Testing in Male Infertility: A Global Survey, Current Guidelines, and Expert Recommendations.

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 from this test. The purpose of this study was to investigate global practices related to indications for SDF testing, compare the relevant professional society guideline recommendations, and provide expert recommendations. MATERIALS AND METHODS: Clinicians managing male infertility were invited to take part in a global online survey on SDF clinical practices. This was conducted following the CHERRIES checklist criteria. The responses were compared to professional society guideline recommendations related to SDF and the appropriate available evidence. Expert recommendations on indications for SDF testing were then formulated, and the Delphi method was used to reach consensus. RESULTS: The survey was completed by 436 experts from 55 countries. Almost 75% of respondents test for SDF in all or some men with unexplained or idiopathic infertility, 39% order it routinely in the work-up of recurrent pregnancy loss (RPL), and 62.2% investigate SDF in smokers. While 47% of reproductive urologists test SDF to support the decision for varicocele repair surgery when conventional semen parameters are normal, significantly fewer general urologists (23%; p=0.008) do the same. Nearly 70% would assess SDF before assisted reproductive technologies (ART), either always or for certain conditions. Recurrent ART failure is a common indication for SDF testing. Very few society recommendations were found regarding SDF testing. CONCLUSIONS: This article presents the largest global survey on the indications for SDF testing in infertile men, and demonstrates diverse practices. Furthermore, it highlights the paucity of professional society guideline recommendations. Expert recommendations are proposed to help guide clinicians.

Controversy and Consensus on the Management of Elevated Sperm DNA Fragmentation in Male Infertility: A Global Survey, Current Guidelines, and Expert Recommendations.

PURPOSE: Sperm DNA fragmentation (SDF) has been associated with male infertility and poor outcomes of assisted reproductive technology (ART). The purpose of this study was to investigate global practices related to the management of elevated SDF in infertile men, summarize the relevant professional society recommendations, and provide expert recommendations for managing this condition. MATERIALS AND METHODS: An online global survey on clinical practices related to SDF was disseminated to reproductive clinicians, according to the CHERRIES checklist criteria. Management protocols for various conditions associated with SDF were captured and compared to the relevant recommendations in professional society guidelines and the appropriate available evidence. Expert recommendations and consensus on the management of infertile men with elevated SDF were then formulated and adapted using the Delphi method. RESULTS: A total of 436 experts from 55 different countries submitted responses. As an initial approach, 79.1% of reproductive experts recommend lifestyle modifications for infertile men with elevated SDF, and 76.9% prescribe empiric antioxidants. Regarding antioxidant duration, 39.3% recommend 4-6 months and 38.1% recommend 3 months. For men with unexplained or idiopathic infertility, and couples experiencing recurrent miscarriages associated with elevated SDF, most respondents refer to ART 6 months after failure of conservative and empiric medical management. Infertile men with clinical varicocele, normal conventional semen parameters, and elevated SDF are offered varicocele repair immediately after diagnosis by 31.4%, and after failure of antioxidants and conservative measures by 40.9%. Sperm selection techniques and testicular sperm extraction are also management options for couples undergoing ART. For most questions, heterogenous practices were demonstrated. CONCLUSIONS: This paper presents the results of a large global survey on the management of infertile men with elevated SDF and reveals a lack of consensus among clinicians. Furthermore, it demonstrates the scarcity of professional society guidelines in this regard and attempts to highlight the relevant evidence. Expert recommendations are proposed to help guide clinicians.

ESHRE guideline: recurrent pregnancy loss: an update in 2022.

STUDY QUESTION: What are the updates for the recommended management of women with recurrent pregnancy loss (RPL) based on the best available evidence in the literature from 2017 to 2022? SUMMARY ANSWER: The guideline development group (GDG) updated 11 existing recommendations on investigations and treatments for RPL, and how care should be organized, and added one new recommendation on adenomyosis investigation in women with RPL. WHAT IS KNOWN ALREADY: A previous ESHRE guideline on RPL was published in 2017 and needs to be updated. STUDY DESIGN SIZE DURATION: The guideline was developed and updated according to the structured methodology for development and update of ESHRE guidelines. The literature searches were updated, and assessments of relevant new evidence were performed. Relevant papers published between 31 March 2017 and 28 February 2022 and written in English were included. Cumulative live birth rate, live birth rate, and pregnancy loss rate (or miscarriage rate) were considered the critical outcomes. PARTICIPANTS/MATERIALS SETTING METHODS: Based on the collected evidence, recommendations were updated and discussed until consensus was reached within the GDG. A stakeholder review was organized after the updated draft was finalized. The final version was approved by the GDG and the ESHRE Executive Committee. MAIN RESULTS AND THE ROLE OF CHANCE: The new version of the guideline provides 39 recommendations on risk factors, prevention, and investigation in couples with RPL, and 38 recommendations on treatments. These includes 62 evidence-based recommendations-of which 33 were formulated as strong recommendations and 29 as conditional-and 15 good practice points. Of the evidence-based recommendations, 12 (19.4%) were supported by moderate-quality evidence. The remaining recommendations were supported by low (34 recommendations; 54.8%), or very low-quality evidence (16 recommendations; 25.8%). Owing to the lack of evidence-based investigations and treatments in RPL care, the guideline also clearly mentions those investigations and treatments that should not be used for couples with RPL. LIMITATIONS REASONS FOR CAUTION: The guidelines have been updated; however, several investigations and treatments currently offered to couples with RPL have not been well studied; for most of these investigations and treatments, a recommendation against using the intervention or treatment was formulated based on insufficient evidence. Future studies may require these recommendations to be revised. WIDER IMPLICATIONS OF THE FINDINGS: The guideline provides clinicians with clear advice on best practice in RPL, based on the best and most recent evidence available. In addition, a list of research recommendations is provided to stimulate further studies in RPL. Still, the absence of a unified definition of RPL is one of the most critical consequences of the limited scientific evidence in the field. STUDY FUNDING/COMPETING INTERESTS: The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings, with the literature searches and with the dissemination of the guideline. The guideline group members did not receive payment.O.B.C. reports being a member of the executive board of the European Society for Reproductive Immunology and has received payment for honoraria for giving lectures about RPL in Australia in 2020. M.G. reports unconditional research and educational grant received by the Centre for Reproductive Medicine, Amsterdam UMC from Guerbet, Merck and Ferring, not related to the presented work. S.L. reports position funding from EXAMENLAB Ltd. and ownership interest by stock or partnership of EXAMENLAB Ltd (CEO). S.Q. reports being a deputy director of Tommy's National centre for miscarriage research, with payment received by the institution for research, staff time, and consumables for research. H.S.N. reports grants with payment to institution from Freya Biosciences ApS, Ferring Pharmaceuticals, BioInnovation Institute, the Danish ministry of Education, Novo Nordic Foundation, Augustinus Fonden, Oda og Hans Svenningsens Fond, Demant Fonden, Ole Kirks Fond, and Independent Research Fund Denmark and speakers' fees for lectures from Ferring Pharmaceuticals, Merck A/S, Astra Zeneca, IBSA Nordic and Cook Medical. She also reports to be an unpaid founder and chairman of a maternity foundation. M.-L.v.d.H. received small honoraria for lectures on RPL care. The other authors have no conflicts of interest to declare. DISCLAIMER: This guideline represents the views of ESHRE, which were achieved after careful consideration of the scientific evidence available at the time of preparation. In the absence of scientific evidence on certain aspects, a consensus between the relevant ESHRE stakeholders has been obtained.Adherence to these clinical practice guidelines does not guarantee a successful or specific outcome, nor does it establish a standard of care. Clinical practice guidelines do not replace the need for application of clinical judgment to each individual presentation, nor variations based on locality and facility type.ESHRE makes no warranty, express or implied, regarding the clinical practice guidelines and specifically excludes any warranties of merchantability and fitness for a particular use or purpose. (Full disclaimer available at www.eshre.eu/guidelines.).

DNA damage in testicular germ cells and spermatozoa. When and how is it induced? How should we measure it? What does it mean?

This review surveys the causes and consequences of DNA damage in the male germ line from spermatogonial stem cells to fully differentiated spermatozoa. Within the stem cell population, DNA integrity is well maintained as a result of excellent DNA surveillance and repair; however, a progressive increase in background mutation rates does occur with paternal age possibly as a result of aberrant DNA repair as well as replication error. Once a germ cell has committed to spermatogenesis, it responds to genetic damage via a range of DNA repair pathways or, if this process fails, by the induction of apoptosis. When fully-differentiated spermatozoa are stressed, they also activate a truncated intrinsic apoptotic pathway which results in the activation of nucleases in the mitochondria and cytoplasm; however, the physical architecture of these cells prevents these enzymes from translocating to the nucleus to induce DNA fragmentation. Conversely, hydrogen peroxide released from the sperm midpiece during apoptosis is able to penetrate the nucleus and induce DNA damage. The base excision repair pathway responds to such damage by cleaving oxidized bases from the DNA, leaving abasic sites that are alkali-labile and readily detected with the comet assay. As levels of oxidative stress increase and these cells enter the perimortem, topoisomerase integrated into the sperm chromatin becomes activated by SUMOylation. Such activation may initially facilitate DNA repair by reannealing double strand breaks but ultimately prepares the DNA for destruction by nucleases released from the male reproductive tract. The abasic sites and oxidized base lesions found in live spermatozoa are mutagenic and may increase the mutational load carried by the offspring, particularly in the context of assisted conception. A variety of strategies are described for managing patients expressing high levels of DNA damage in their spermatozoa, to reduce the risks such lesions might pose to offspring health.

Revisiting the impact of varicocele and its treatments on male fertility.

Varicocele is one of the most common, yet treatable, causes of male infertility. Varicoceles are present in more than 40% of infertile men with primary infertility, a figure that increases with age. Varicoceles impair semen parameters and sperm DNA and are linked with lower pregnancy and live birth rates. Until recently, men had seldom been examined in male fertility workups. This is changing as urologists have become recognized as team members in infertility. Hence identification and treatment are available as never before. Furthermore, as men become aware that they are as likely as their female partners to be infertile, they want equal 'couple care', requesting urological referrals as they realize that they can improve their semen quality and chances of fatherhood without or before fertility treatment. There is now a greater understanding of the mechanisms of varicocele-induced damage by oxidative stress, using sperm DNA as a sensitive biomarker of sperm quality. There is a current consensus that varicocele is linked to poor semen and repair improves semen and sperm DNA quality. Evidence is strengthening to indicate that varicocele repair increases pregnancy and live birth rates in natural conception and following fertility treatment.

Sperm selection with hyaluronic acid improved live birth outcomes among older couples and was connected to sperm DNA quality, potentially affecting all treatment outcomes.

STUDY QUESTION: What effects did treatment using hyaluronic acid (HA) binding/selection prior to ICSI have on clinical outcomes in the Hyaluronic Acid Binding sperm Selection (HABSelect) clinical trial? SUMMARY ANSWER: Older women randomized to the trial's experimental arm (selection of sperm bound to immobilized (solid-state) HA) had the same live birth rates as younger women, most likely a result of better avoidance of sperm with damaged DNA. WHAT IS KNOWN ALREADY: Recent randomized controlled trials (RCTs) investigating the efficacy of HA-based sperm selection prior to ICSI, including HABSelect, have consistently reported reductions in the numbers of miscarriages among couples randomized to the intervention, suggesting a pathological sperm-mediated factor mitigated by prior HA-binding/selection. The mechanism of that protection is unknown. STUDY DESIGN, SIZE, DURATION: The original HABSelect Phase 3 RCT ran from 2014 to 2017 and included 2752 couples from whom sperm samples used in control (ICSI) and intervention (Physiological IntraCytoplasmic Sperm Injection; PICSI) arms of the trial were stored frozen for later assessment of DNA quality (DNAq). The trial overlapped with its mechanistic arm, running from 2016 to 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: As miscarriage reduction was a significant secondary outcome of the trial, samples (n = 1247) selected for the mechanistic analysis were deliberately enriched for miscarriage outcomes (n = 92 or 7.4%) from a total of 154 miscarriages (5.6%) among all (n = 2752) couples randomized by stratified random sampling. Values from fresh semen samples for sperm concentration (mml), percentage forward progressive motility and percentage HA-binding score (HBS) were obtained before being processed by differential density gradient centrifugation or (rarely) by swim-up on the day of treatment. Surplus sperm pellets were recovered, aliquoted and cryopreserved for later analysis of DNAq using slide-based Comet, TUNEL, acridine orange (AO) and the sperm chromatin dispersion (SCD) assays. Following their classification into normal and abnormal sample subcategories based on reference values for sperm concentration and motility, relationships with HBS and DNAq were examined by Spearman correlation, Student's t-tests, Mann Whitney U tests, and logistic regression (univariable and multivariable). Parsimonious selection enabled the development of models for exploring and explaining data trends. Potential differences in future cumulative pregnancy rates relating to embryo quality were also explored. MAIN RESULTS AND THE ROLE OF CHANCE: Results from the 1247 sperm samples assayed for HBS and/or DNAq, generated data that were considered in relation to standard physiological measures of (sperm) vitality and to treatment outcomes. All measures of HBS and DNAq discriminated normal from abnormal sperm samples (P < 0.001). SCD correlated negatively with the Comet (r = -0.165; P < 0.001) and TUNEL assays (r = -0.200; P < 0.001). HBS correlated negatively with AO (r = -0.211; P < 0.001), Comet (r = -0.127; P < 0.001) and TUNEL (r = -0.214; P < 0.001) and positively with SCD (r = 0.255; P < 0.001). A model for predicting live birth (and miscarriage) rates included treatment allocation (odds ratio: OR 2.167, 95% CI 1.084-4.464, P = 0.031), female age (OR 0.301, 95% CI 0.133-0.761, P = 0.013, per decade) and the AO assay (OR 0.79, 95% CI 0.60-1. 02.761, P = 0.073, per 10 points rise). A model predicting the expected rate of biochemical pregnancy included male age (OR 0.464, 95% CI 0.314-0.674, P < 0.001, per decade) and the SCD assay (OR 1.04, 95% CI 1.007-1.075, P = 0.018, per 10 point rise). A model for conversion from biochemical to clinical pregnancy did not retain any significant patient or assay variables. A model for post-injection fertilization rates included treatment allocation (OR 0.83, 95% CI 0.75-0.91, P < 0.001) and the Comet assay (OR 0.950, 95% CI 0.91-1.00, P = 0.041). LIMITATIONS, REASONS FOR CAUTION: HABSelect was a prospective RCT and the mechanistic study group was drawn from its recruitment cohort for retrospective analysis, without the full benefit of randomization. The clinical and mechanistic aspects of the study were mutually exclusive in that measures of DNAq were obtained from residual samples and not from HA-selected versus unselected sperm. Models for fitting mechanistic with baseline and other clinical data were developed to compensate for variable DNAq data quality. HABSelect used a solid-state version of PICSI and we did not assess the efficacy of any liquid-state alternatives. PICSI reduced fertilization rates and did not improve the outlook for cumulative pregnancy rates. WIDER IMPLICATIONS OF THE FINDINGS: Notwithstanding the interventional effect on fertilization rates and possibly blastocyst formation (neither of which influenced pregnancy rates), poor sperm DNAq, reflected by lower HBS, probably contributed to the depression of all gestational outcomes including live births, in the HABSelect trial. The interventional avoidance of defective sperm is the best explanation for the equalization in live birth rates among older couples randomized to the trial's PICSI arm. As patients going forward for assisted conception cycles globally in future are likely to be dominated by an older demographic, HA-based selection of sperm for ICSI could be considered as part of their treatment plan. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by the National Institute for Health Research (NIHR) EME (Efficacy and Mechanism Evaluation)-11-14-34. National Research Ethics Service approval 11/06/2013: 13/YH/0162. S.L. is CEO of ExamenLab Ltd (company number NI605309). TRIAL REGISTRATION NUMBER: ISRCTN99214271.

A Comprehensive Guide to Sperm Recovery in Infertile Men with Retrograde Ejaculation.

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. The treatment approaches outlined are determined by the cause. Alkalinizing urinary pH with oral medications or by adding sperm wash media into the bladder prior to ejaculation may preserve the viability of the sperm. This article provides a step-by-step guide to diagnose RE and the optimal techniques to retrieve sperm.

Relevance of Leukocytospermia and Semen Culture and Its True Place in Diagnosing and Treating Male Infertility.

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 poor sperm quality, increased level of sperm DNA fragmentation and low fertility potential. The presence of leukocytes and pathogens in the semen may be a sign of infection and/or localized inflammatory response in the male genital tract and the accessory glands. Common uro-pathogens including Chlamydia trachomatis, Ureaplasma urealyticum, Neisseria gonorrhoeae, Mycoplasma hominis, and Escherichia coli can cause epididymitis, epididymo-orchitis, or prostatitis. The relationship between leukocytospermia and infection is unclear. Therefore, we describe the pathogens responsible for male genital tract infections and their association with leukocytospermia. The review also examines the diagnostic tests available to identify seminal leukocytes. The role of leukocytospermia in male infertility and its management is also discussed.

Sperm Morphology Assessment in the Era of Intracytoplasmic Sperm Injection: Reliable Results Require Focus on Standardization, Quality Control, and Training.

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 to the highly subjective nature of their evaluation. ICSI is the choice of treatment when sperm morphology is severely abnormal (teratozoospermic). Hence, the standardization of laboratory protocols for sperm morphology evaluation represents a fundamental step to ensure reliable, accurate and consistent laboratory results that avoid misdiagnoses and inadequate treatment of the infertile patient. This article aims to promote standardized laboratory procedures for an accurate evaluation of sperm morphology, including the establishment of quality control and quality assurance policies. Additionally, the clinical importance of sperm morphology results in assisted reproductive outcomes is discussed, along with the clinical management of teratozoospermic patients.

SARS-CoV-2 pandemic and repercussions for male infertility patients: A proposal for the individualized provision of andrological services.

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 propose that the same permissive approach for sperm banking granted for men with cancer is expanded to other groups of vulnerable patients. These groups include infertility patients (eg, azoospermic and cryptozoospermic) undergoing medical or surgical treatment to improve sperm quantity and quality, as well as males of reproductive age affected by inflammatory and systemic auto-immune diseases who are about to start treatment with gonadotoxic drugs or who are under remission. In both scenarios, the "fertility window" may be transitory; postponing diagnostic semen analysis and sperm banking in these men could compromise the prospects of biological parenthood. Moreover, we provide recommendations on how to continue the provision of andrological services in a considered manner and a safe environment. Our opinion is timely and relevant given the fact that fertility services are currently rated as of low priority in most countries.

Sperm DNA fragmentation is a novel biomarker for early pregnancy loss.

RESEARCH QUESTION: Spontaneous pregnancy loss affects 10-15% of couples, with 1-2% suffering recurrent pregnancy loss and 50% of miscarriages remaining unexplained. Male genomic integrity is essential for healthy offspring, meaning sperm DNA quality may be important in maintaining a pregnancy. Does sperm DNA fragmentation measured by alkaline Comet assay act as a biomarker for early pregnancy loss? DESIGN: Sperm DNA fragmentation was measured by alkaline Comet test in 76 fertile donors and 217 men whose partners had recently experienced miscarriage. Couples were divided into five groups for analysis: one miscarriage after spontaneous conception; two or more miscarriages after spontaneous conception; one miscarriage after fertility treatment; two or more miscarriages after fertility treatment and biochemical pregnancy. RESULTS: Receiver operator characteristic curve analysis was used to determine ability of the average Comet score (ACS), low Comet score (LCS) and high Comet score (HCS) to diagnose miscarriage and develop clinical thresholds comparing men whose partners have miscarried with men with recently proven fertility. Male partners of women who had miscarried had higher sperm DNA damage (ACS 33.32 ± 0.57%) than fertile men (ACS 14.87 ± 0.66%; P < 0.001). Average Comet score, HCS and LCS all have promise as being highly predictive of sporadic and recurrent miscarriage using clinical thresholds from comparisons with fertile men's spermatozoa: receiver operating characteristic curve AUC for ACS ≥26%, 0.965; LCS ≤70%, 0.969; HCS ≥2%, 0.883; P <0.0001. CONCLUSIONS: Sperm DNA damage measured by the alkaline Comet has promise as a robust biomarker for sporadic and recurrent miscarriage after spontaneous or assisted conception, and may provide novel diagnoses and guidance for future fertility pathways.

Sperm DNA fragmentation testing: Summary evidence and clinical practice recommendations.

We herein summarise the evidence concerning the impact of sperm DNA fragmentation in various clinical infertility scenarios and the advances on sperm DNA fragmentation tests. The collected evidence was used to formulate 41 recommendations. Of these, 13 recommendations concern technical aspects of sperm DNA fragmentation testing, including pre-analytical information, clinical thresholds and interpretation of results. The remaining 28 recommendations relate to indications for sperm DNA fragmentation testing and clinical management. Clinical scenarios like varicocele, unexplained infertility, idiopathic infertility, recurrent pregnancy loss, intrauterine insemination, in vitro fertilisation/intracytoplasmic sperm injection, fertility counselling for men with infertility risk factors and sperm cryopreservation have been contemplated. The bulk evidence supporting the recommendations has increased in recent years, but it is still of moderate to low quality. This guideline provides clinicians with advice on best practices in sperm DNA fragmentation testing. Also, recommendations are provided on possible management strategies to overcome infertility related to sperm DNA fragmentation, based on the best available evidence. Lastly, we identified gaps in knowledge and opportunities for research and elaborated a list of recommendations to stimulate further investigation.

Novel use of COMET parameters of sperm DNA damage may increase its utility to diagnose male infertility and predict live births following both IVF and ICSI.

STUDY QUESTION: Do the Comet parameters of the proportions of sperm with low or high DNA damage improve the power of the test in the diagnosis of male infertility and/or prediction of IVF and ICSI live birth rates? SUMMARY ANSWER: The mean Comet score and the scores for proportions of sperm with high or low DNA damage were useful in diagnosing male infertility and provided additional discriminatory information for the prediction of both IVF and ICSI live births. WHAT IS KNOWN ALREADY: Sperm DNA damage impacts adversely on male fertility and IVF outcomes. STUDY DESIGN, SIZE, DURATION: A retrospective study was performed involving a total of 457 participants (381 patients and 76 fertile donors). Data was collected from a fertility clinic between 2015 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 381 consecutive male partners of couples attending for ART and 76 fertile donors were included in the study. DNA fragmentation was measured by the alkaline Comet assay. Receiver operator characteristic curve analysis (area under the ROC curve (AUC)) was used to determine the value of average Comet score (ACS), low Comet score (LCS) and high Comet score (HCS) to diagnose male factor infertility. In total, 77 IVF and 226 ICSI cycles were included to determine thresholds for each parameter (AUC analysis) and to compare live birth rates (LBRs) following each ART. MAIN RESULTS AND THE ROLE OF CHANCE: ACS, HCS and LCS were predictive of male infertility (AUC > 0.9, P < 0.0001). IVF LBRs declined once DNA damage exceeded the threshold levels. HCS showed the sharpest decline. Following ICSI, the highest LBRs were in men whose DNA damage levels approached the fertile range. Trends differed in IVF. LBRs decreased as damage increased whereas in ICSI the LBRs decreased but then remained stable. LIMITATIONS, REASONS FOR CAUTION: Since this is the first study to show the impact of sperm DNA damage on ICSI live births, a prospective study should be performed (stratifying patients to IVF or ICSI based on these thresholds) to validate this study. WIDER IMPLICATIONS OF THE FINDINGS: Our study presents novel information towards elucidating the genetic basis of male infertility and secondly on relevance of the extent of DNA damage as an impending factor in both IVF and ICSI success. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by Examenlab Ltd, The Lister Clinic, Cryos International and Imperial College London NHS Trust. No external funding was obtained for this study. SL and KL are employees of Examenlab Ltd, a university spin-out company with a commercial interest in sperm DNA damage. No other author has a conflict of interest to declare. TRIAL REGISTRATION NUMBER: Non-applicable.

Physiological, hyaluronan-selected intracytoplasmic sperm injection for infertility treatment (HABSelect): a parallel, two-group, randomised trial.

BACKGROUND: Sperm selection strategies aimed at improving success rates of intracytoplasmic sperm injection (ICSI) include binding to hyaluronic acid (herein termed hyaluronan). Hyaluronan-selected sperm have reduced levels of DNA damage and aneuploidy. Use of hyaluronan-based sperm selection for ICSI (so-called physiological ICSI [PICSI]) is reported to reduce the proportion of pregnancies that end in miscarriage. However, the effect of PICSI on livebirth rates is uncertain. We aimed to investigate the efficacy of PICSI versus standard ICSI for improving livebirth rates among couples undergoing fertility treatment. METHODS: This parallel, two-group, randomised trial included couples undergoing an ICSI procedure with fresh embryo transfer at 16 assisted conception units in the UK. Eligible women (aged 18-43 years) had a body-mass index of 19-35 kg/m2 and a follicle-stimulating hormone (FSH) concentration of 3·0-20·0 mIU/mL or, if no FSH measurement was available, an anti-müllerian hormone concentration of at least 1·5 pmol/L. Eligible men (aged 18-55 years) had not had a vasovasostomy or been treated for cancer in the 24 months before recruitment and were able, after at least 3 days of sexual abstinence, to produce freshly ejaculated sperm for the treatment cycle. Couples were randomly assigned (1:1) with an online system to receive either PICSI or a standard ICSI procedure. The primary outcome was full-term (≥37 weeks' gestational age) livebirth, which was assessed in all eligible couples who completed follow-up. This trial is registered, number ISRCTN99214271. FINDINGS: Between Feb 1, 2014, and Aug 31, 2016, 2772 couples were randomly assigned to receive PICSI (n=1387) or ICSI (n=1385), of whom 2752 (1381 in the PICSI group and 1371 in the ICSI group) were included in the primary analysis. The term livebirth rate did not differ significantly between PICSI (27·4% [379/1381]) and ICSI (25·2% [346/1371]) groups (odds ratio 1·12, 95% CI 0·95-1·34; p=0·18). There were 56 serious adverse events in total, including 31 in the PICSI group and 25 in the ICSI group; most were congenital abnormalities and none were attributed to treatment. INTERPRETATION: Compared with ICSI, PICSI does not significantly improve term livebirth rates. The wider use of PICSI, therefore, is not recommended at present. FUNDING: National Institute for Health Research Efficacy and Mechanism Evaluation Programme.