The relationship between isolated teratozoospermia and clinical pregnancy after in vitro fertilization with or without intracytoplasmic sperm injection: a systematic review and meta-analysis

High rate of isolated teratospermia in a population of fertile men and the questionable clinical utility of sperm morphology

Objective

To better understand the impact of sperm morphology on fertility by assessing sperm morphology in a population of known fertile men.

Design

A prospective cohort study.

Setting

Fertility center associated with the university.

Patients

Healthy men >18 years of age were recruited to provide one semen sample before a vasectomy appointment scheduled between March 2020 and November 2022. Patients were included in the study when they had at least one biologic child and no history of difficulty achieving pregnancy or fertility procedures.

Interventions

None.

Main Outcome Measures

Sperm morphology.

Results

A total of 68 patients (mean age 36.7 years) were included. Thirty-eight (55.9%) patients had 3% or lower normal sperm morphology, including two patients who had 0 normal morphology. The most common morphologic abnormalities were head-shaped defects (n = 59, 84.3%), followed by coiled tails (n = 14, 20.3%). Count, concentration, motility, and progressive motility were normal in >90% of patients.

Conclusions

More than half (55.9%) of fertile male patients had lower than normal sperm morphology in our study. The results of our study further question the clinical relevance of sperm morphology on fertility outcomes and when the current approach in assessing morphology is too strict.

Normal sperm head morphometric reference values in fertile Asian males

Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive potential. Several criteria are available to analyze sperm head morphology, but they are limited by poor methodology comparability and population applicability. This study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads in fertile Asian males. An automated sperm morphology analysis system captured 23 152 stained spermatozoa from confirmed fertile males. Of these samples, 1856 sperm head images were annotated by three experienced laboratory technicians as "normal". We employed 14 novel morphometric features to describe sperm head size (head length, head width, length/width ratio, and girth), shape (ellipse intersection over union, girth intersection over union, short-axis symmetry, and long-axis symmetry), area (head, acrosome, postacrosomal areas, and acrosome area ratio), and degrees of acrosome and nuclear uniformity. This straight-forward method for the morphometric analysis of sperm by accurate visual measurements is clinically applicable. The measured parameters present valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian males. The presented detailed measurement data will be valuable for interlaboratory comparisons and technician training. In vitro fertilization and andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing male fertilization potential.

Sperm morphology value in assisted reproduction: dismantling an enigma and key takeaways for the busy clinician

The ideal morphology of the sperm cell was initially described based on the characteristics of sperm able to migrate through the endocervical canal assuming these had the best fertilization potential. Sperm morphology assessment has moved over the years toward stricter criteria based on the findings from studies that underline its value in successful reproductive outcomes. While treatment options are clear for some conditions related to abnormal sperm morphology, the value of sperm morphology in assisted reproduction requires further investigation. The objective of this review is to offer care providers updated guidance for choosing appropriate treatment strategies based on sperm morphology assessment and morphological deviations. Issues to be considered for a reliable determination and interpretation of sperm morphology using the current thresholds and criteria are discussed. In addition, key knowledge on morphological abnormalities relevant to the clinical care of infertile patients, distinguishing between monomorphic and polymorphic forms as well as the isolated or non-isolated occurrence of teratozoospermia in semen is presented. Furthermore, the impact of impaired morphology on assisted reproductive technique outcomes is summarized in light of the latest research.

Intracytoplasmic sperm injection vs. in-vitro fertilization in couples in whom the male partners had a semen analysis within normal reference ranges: An open debate

During recent decades, the application of intracytoplasmic sperm injection has increased considerably worldwide, especially in couples with non-male factor infertility. However, several studies analyzing the broad use of intracytoplasmic sperm injection, even in cases with a normal semen analysis, have collectively demonstrated no benefits compared to conventional in-vitro fertilization. Currently, there is insufficient evidence to support the intracytoplasmic sperm injection technique vs. in-vitro fertilization in cases of poor ovarian response or a low number of oocytes collected, or in patients with advanced maternal age. Since the intracytoplasmic sperm injection technique is more operator-dependent and invasive, its use should only be recommended in cases of male-factor infertility. There is some evidence showing that intracytoplasmic sperm injection is linked with an increased risk of birth defects. Albeit this evidence is limited, and currently it is not possible to draw a firm conclusion on these concerns, we do believe that these risks should be rigorously investigated. Thus, this review aims to clarify the debate on the application of the intracytoplasmic sperm injection procedure, as compared to standard in-vitro fertilization, in those assisted reproductive technology cycles without a clear male factor infertility. Furthermore, we try to clarify whether intracytoplasmic sperm injection would result in a higher live birth rate than in-vitro fertilization, in couples with non-male factor infertility.

Zinc oxide nanoparticles-induced testis damage at single-cell resolution: Depletion of spermatogonia reservoir and disorder of Sertoli cell homeostasis

The widespread application of zinc oxide nanoparticles (ZnO NPs) in our daily life has initiated an enhanced awareness of their biosafety concern. An incredible boom of evidence of organismal disorder has accumulated for ZnO NPs, yet there has been no relevant study at the single-cell level. Here, we profiled > 28,000 single-cell transcriptomes and assayed > 25,000 genes in testicular tissues from two healthy Sprague Dawley (SD) rats and two SD rats orally exposed to ZnO NPs. We identified 10 cell types in the rat testis. ZnO NPs had more deleterious effects on spermatogonia, Sertoli cells, and macrophages than on the other cell types. Cell-cell communication analysis indicated a sharp decrease of interaction intensity for all cell types except macrophages in the ZnO NPs group than in the control group. Interestingly, two distinct maturation states of spermatogonia were detected during pseudotime analysis, and ZnO NPs induced reservoir exhaustion of undifferentiated spermatogonia. Mechanically, ZnO NPs triggered fatty acid accumulation in GC-1 cells through protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling and peroxisome proliferator-activated receptor alpha (PPARα)/acyl-CoA oxidase 1 (Acox1) axis, contributing to cell apoptosis. In terms of Sertoli cells, downregulated genes were highly enriched for tight junction. In vitro and in vivo experiments verified that ZnO NPs disrupted blood-testis barrier formation and growth factors synthesis, which subsequently inhibited the proliferation and induced the apoptosis of spermatogonia. As for the macrophages, ZnO NPs activated oxidative stress of Raw264.7 cells through nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway and promoted cell apoptosis through extracellular signal-regulated kinase (ERK) 1/2 pathway. Collectively, our work reveals the cell type-specific and cellularly heterogenetic mechanism of ZnO NPs-induced testis damage and paves the path for identifying putative biomarkers and therapeutics against this disorder.

From Diagnosis to Treatment: Comprehensive Care by Reproductive Urologists in Assisted Reproductive Technology

Infertility is a global health concern, with male factors playing an especially large role. Unfortunately, however, the contributions made by reproductive urologists in managing male infertility under assisted reproductive technology (ART) often go undervalued. This narrative review highlights the important role played by reproductive urologists in diagnosing and treating male infertility as well as any barriers they face when providing services. This manuscript presents a comprehensive review of reproductive urologists' role in managing male infertility, outlining their expertise in diagnosing and managing male infertility as well as reversible causes and performing surgical techniques such as sperm retrieval. This manuscript investigates the barriers limiting urologist involvement such as limited availability, awareness among healthcare professionals, and financial constraints. This study highlights a decrease in male fertility due to lifestyle factors like sedentary behavior, obesity, and substance abuse. It stresses the significance of conducting an evaluation process involving both male and female partners to identify any underlying factors contributing to infertility and to identify patients who do not require any interventions beyond ART. We conclude that engaging urologists more effectively in infertility management is key to optimizing fertility outcomes among couples undergoing assisted reproductive technology treatments and requires greater education among healthcare providers regarding the role urologists and lifestyle factors that could have an effect on male fertility.

The use of ICSI in ART: evidence for practice

This article reviews the evidence regarding the safety and efficacy of intra-cytoplasmic sperm injection (ICSI). It provides evidence-based clinical and laboratory guidelines and recommendations for use of ICSI within an assisted reproductive technology (ART) service. The guidelines address the evidence for the use of ICSI rather than conventional IVF (cIVF); the use of ART techniques supplementary to ICSI; and risks associated with ICSI. This article is not intended to be the only approved standard of practice or to dictate an exclusive course of treatment. Other plans of management may be appropriate, taking into account the needs and medical history of the patient, available resources, and institutional or clinical practice limitations.

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.

Poor reproducibility of percentage of normally shaped sperm using the World Health Organization Fifth Edition strict grading criteria

Objective

To determine the reproducibility of the World Health Organization Fifth Edition (WHO5) strict grading methodology by comparing the percentage of morphologically normal sperm (PNS) recorded by the core laboratory with results obtained at the fertility centers participating in a multisite clinical trial.

Design

Secondary cohort analysis of data from the Males, Antioxidants, and Infertility trial.

Setting

Fertility centers.

Patients

Semen values of 171 men participating in a multicenter, double-blind, randomized, placebo-controlled trial evaluating the effect of antioxidants on male fertility.

Interventions

Not applicable.

Main Outcome Measures

Strict morphology expressed as PNS as determined at each fertility center and the core central laboratory for the same semen sample.

Results

No correlation was found in the PNS values for the same semen sample between the core laboratory and fertility center laboratories either as a group or by individual site. Interobserver agreement was similarly low (κ = 0.05 and 0.15) between the core and fertility laboratories as a group for strict morphology, categorized by the WHO5 lower reference limits of 4% and 0, respectively. Moderate agreement was found between the core and 2 individual fertility laboratories for the cutoff value of 0 (κ = 0.42 and 0.57). The remainder of the comparisons demonstrated poor to fair agreement.

Conclusions

Strict morphology grading using the WHO5 methodology demonstrated overall poor reproducibility among a cohort of experienced fertility laboratories. This lack of correlation and agreement in the PNS values calls into question the reproducibility, and thereby the potential applicability, of sperm strict morphology testing.

Contemporary Use of ICSI and Epigenetic Risks to Future Generations

Since the birth of Louise Brown in 1978 via IVF, reproductive specialists have acquired enormous knowledge and refined several procedures, which are nowadays applied in assisted reproductive technology (ART). One of the most critical steps in this practice is the fertilization process. In the early days of IVF, a remarkable concern was the unpleasant outcomes of failed fertilization, overtaken by introducing intracytoplasmic sperm injection (ICSI), delineating a real breakthrough in modern ART. ICSI became standard practice and was soon used as the most common method to fertilize oocytes. It has been used for severe male factor infertility and non-male factors, such as unexplained infertility or advanced maternal age, without robust scientific evidence. However, applying ICSI blindly is not free of potential detrimental consequences since novel studies report possible health consequences to offspring. DNA methylation and epigenetic alterations in sperm cells of infertile men might help explain some of the adverse effects reported in ICSI studies on reproductive health in future generations. Collected data concerning the health of ICSI children over the past thirty years seems to support the notion that there might be an increased risk of epigenetic disorders, congenital malformations, chromosomal alterations, and subfertility in babies born following ICSI compared to naturally conceived children. However, it is still to be elucidated to what level these data are associated with the cause of infertility or the ICSI technique. This review provides an overview of epigenetic mechanisms and possible imprinting alterations following the use of ART, in particular ICSI. It also highlights the sperm contribution to embryo epigenetic regulation and the risks of in vitro culture conditions on epigenetic dysregulation. Lastly, it summarizes the literature concerning the possible epigenetic disorders in children born after ART.

The association of impaired semen quality and pregnancy rates in assisted reproduction technology cycles: Systematic review and meta-analysis

Some studies suggest a relationship between semen quality and pregnancy rates of assisted reproduction technologies (ART). Others have questioned the utility of semen quality as proxy for fertility in couples attempting to conceive with or without assistance. We aimed to investigate the current body of evidence which correlates semen parameters and clinical pregnancy among couples utilizing ART (i.e. in vitro fertilization [IVF], intracytoplasmic sperm injection [ICSI]) through a systematic review and meta‐analysis of cross‐sectional and retrospective cohort studies. Pooled Odd Ratio (OR) for oligo‐, astheno‐ and teratospermic compared to normospermic number of ART cycles were calculated among. Meta‐regression and sub‐group analysis were implemented to model the contribution of clinical/demographic and laboratory standards differences among the studies. Overall, 17 studies were analysed representing 17,348 cycles were analysed. Pooled OR for impaired sperm concentration, motility and morphology was 1 (95%Confidence Interval [CI]: 0.97–1.03), 0.88 (95%CI: 0.73–1.03) and 0.88 (95%CI: 0.75–1) respectively. Further analysis on sperm morphology showed no differences with regard of IVF versus ICSI (p = 0.14) nor a significant correlation with rising reference thresholds (Coeff: −0.02, p = 0.38). A temporal trend towards a null association between semen parameters and clinical pregnancy was observed over the 20‐year observation period (Coeff: 0.01, p = 0.014). The current analysis found no association between semen quality (as measured by concentration, motility or morphology) and clinical pregnancy rates utilizing ART. Future investigations are necessary to explore the association between semen parameters and other ART outcomes (e.g. fertilization, implantation, birth and perinatal health).

Simulating nature in sperm selection for assisted reproduction

Sperm selection in the female reproductive tract (FRT) is sophisticated. Only about 1,000 sperm out of millions in an ejaculate reach the fallopian tube and thus have a chance of fertilizing an oocyte. In assisted reproduction techniques, sperm are usually selected using their density or motility, characteristics that do not reflect their fertilization competence and, therefore, might result in failure to fertilize the oocyte. Although sperm processing in in vitro fertilization (IVF) and intrauterine insemination (IUI) bypasses many of the selection processes in the FRT, selection by the cumulus mass and the zona pellucida remain intact. By contrast, the direct injection of a sperm into an oocyte in intracytoplasmic sperm injection (ICSI) bypasses all natural selection barriers and, therefore, increases the risk of transferring paternal defects such as fragmented DNA and genomic abnormalities in sperm to the resulting child. Research into surrogate markers of fertilization potential and into simulating the natural sperm selection processes has progressed. However, methods of sperm isolation - such as hyaluronic acid-based selection and microfluidic isolation based on sperm tactic responses - use only one or two parameters and are not comparable with the multistep sperm selection processes naturally occurring within the FRT. Fertilization-competent sperm require a panel of molecules, including zona pellucida-binding proteins and ion channel proteins, that enable them to progress through the FRT to achieve fertilization. The optimal artificial sperm selection method will, therefore, probably need to use a multiparameter tool that incorporates the molecular signature of sperm with high fertilization potential, and their responses to external cues, within a microfluidic system that can replicate the physiological processes of the FRT in vitro.

Are sperm parameters able to predict the success of assisted reproductive technology? A retrospective analysis of over 22,000 assisted reproductive technology cycles

Background

An explosive increase in couples attending assisted reproductive technology has been recently observed, despite an overall success rate of about 20%–30%. Considering the assisted reproductive technology‐related economic and psycho‐social costs, the improvement of these percentages is extremely relevant. However, in the identification of predictive markers of assisted reproductive technology success, male parameters are largely underestimated so far.

Study design

Retrospective, observational study.

Objectives

To evaluate whether conventional semen parameters could predict assisted reproductive technology success.

Materials and methods

All couples attending a single third‐level fertility center from 1992 to 2020 were retrospectively enrolled, collecting all semen and assisted reproductive technology parameters of fresh cycles. Fertilization rate was the primary end‐point, representing a parameter immediately dependent on male contribution. Pregnancy and live birth rates were considered in relation to semen variables. Statistical analyses were performed using the parameters obtained according to the World Health Organization manual editions used for semen analysis.

Results

Note that, 22,013 in vitro fertilization and intracytoplasmic sperm injection cycles were considered. Overall, fertilization rate was significantly lower in patients with abnormal semen parameters compared to normozoospermic men, irrespective of the World Health Organization manual edition. In the in vitro fertilization setting, both progressive motility (p = 0.012) and motility after capacitation (p = 0.002) significantly predicted the fertilization rate (statistical accuracy = 71.1%). Sperm motilities also predicted pregnancy (p < 0.001) and live birth (p = 0.001) rates. In intracytoplasmic sperm injection cycles, sperm morphology predicted fertilization rate (p = 0.001, statistical accuracy = 90.3%). Sperm morphology significantly predicted both pregnancy (p < 0.001) and live birth (p < 0.001) rates and a cut‐off of 5.5% was identified as a threshold to predict clinical pregnancy (area under the curve = 0.811, p < 0.001).

Discussion

Interestingly, sperm motility plays a role in predicting in vitro fertilization success, while sperm morphology is the relevant parameter in intracytoplasmic sperm injection cycles. These parameters may be considered reliable tools to measure the male role on ART outcomes, potentially impacting the clinical management of infertile couples.

Diagnostics and Management of Male Infertility in Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD), a disease caused by the malfunction of motile cilia, manifests mainly with chronic recurrent respiratory infections. In men, PCD is also often associated with infertility due to immotile sperm. Since causative mutations for PCD were identified in over 50 genes, the role of these genes in sperm development should be investigated in order to understand the effect of PCD mutations on male fertility. Previous studies showed that different dynein arm heavy chains are present in respiratory cilia and sperm flagellum, which may partially explain the variable effects of mutations on airways and fertility. Furthermore, recent studies showed that male reproductive tract motile cilia may play an important part in sperm maturation and transport. In some PCD patients, extremely low sperm counts were reported, which may be due to motile cilia dysfunction in the reproductive tract rather than problems with sperm development. However, the exact roles of PCD genes in male fertility require additional studies, as do the treatment options. In this review, we discuss the diagnostic and treatment options for men with PCD based on the current knowledge.

In vitro fertilisation (IVF) versus intracytoplasmic sperm injection (ICSI) in patients without severe male factor infertility: study protocol for the randomised, controlled, multicentre trial INVICSI

INTRODUCTION

Over the last decades, the use of intracytoplasmic sperm injection (ICSI) has increased, even among patients without male factor infertility. The increase has happened even though there is no evidence to support that ICSI results in higher live birth rates compared with conventional in vitro fertilisation (IVF) in cases with nonmale factor infertility. The lack of robust evidence on an advantage of using ICSI over conventional IVF in these patients is problematic since ICSI is more invasive, complex and requires additional resources, time and effort. Therefore, the primary objective of the IVF versus ICSI (INVICSI) study is to determine whether ICSI is superior to standard IVF in patients without severe male factor infertility. The primary outcome measure is first live birth from fresh and frozen-thawed transfers after one stimulated cycle. Secondary outcomes include fertilisation rate, ongoing pregnancy rate, birth weight and congenital anomalies.

METHODS AND ANALYSIS

This is a two-armed, multicentre, randomised, controlled trial. In total, 824 couples/women with infertility without severe male factor will be recruited and allocated randomly into two groups (IVF or ICSI) in a 1:1 ratio. Participants will be randomised in variable block sizes and stratified by trial site and age. The main inclusion criteria are (1) no prior IVF/ICSI treatment, (2) male partner sperm with an expected count of minimum 2 million progressive motile spermatozoa following density gradient purification on the day of oocyte pick up and (3) age of the woman between 18 and 42 years.

ETHICS AND DISSEMINATION

The study will be performed in accordance with the ethical principles in the Helsinki Declaration. The study is approved by the Scientific Ethical Committee of the Capital Region of Denmark. Study findings will be presented, irrespectively of results at international conferences and submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04128904. Pre-results.

Correlation among isolated teratozoospermia, sperm DNA fragmentation and markers of systemic inflammation in primary infertile men

Aim

To assess the prevalence of isolated teratozoospermia (iTZS) in a cohort of infertile and fertile men; explore the relationship between iTZS, inflammatory parameters and sperm DNA fragmentation index (SDF) in the same cohort.

Materials and methods

1824 infertile men and 103 fertile controls. Semen analysis, the neutrophil-to-lymphocyte ratio (NLR) and serum hormones were investigated. DFI was tested in infertile men only. According to 2010 WHO semen analysis, patients were categorized in 3 sub-groups of isolated sperm defects: isolated oligozoospermia (iOZS), isolated asthenozoospermia (iAZS) and iTZS. Descriptive statistics and linear regression models tested the association between clinical variables and inflammatory markers.

Results

Among infertile men, iAZS, iTZS, and iOZS were found in 13.9%, 11.9% and 4.1% participants, respectively. iTZS was found in 37 (35.9%) fertile men. Infertile men with iTZS had higher NLR values than those with iOZS, iAZS and men with normal semen parameters (all p<0.001). FSH and LH were higher and inhibin B lower in iOZS infertile men compared to all other groups (p≤0.001). Hormonal characteristics were similar between iTZS infertile and fertile men. Similarly, iTZS infertile men had higher SDF than all other groups (all p<0.001). Infertile men with iTZS had higher NLR values than fertile men with iTZS (p<0.01). Linear regression analysis showed that, in infertile men, iTZS was associated with SDF and NLR (all p≤0.01).

Conclusions

iTZS was found in 11.9% of infertile men but it was even more prevalent in fertile controls. Infertile men with iTZS had higher NLR than fertile controls and increased SDF values than infertile participant with iAZS, iOZS, or normal semen parameters. No differences in hormonal characteristics were found between infertile and fertile men with iTZS.

Assessing the clinical value of the Kruger strict morphology criteria over the World Health Organization fourth edition criteria

Objective

To assess if the newer Kruger strict morphology (WHO5; normal ≥4%) adds any clinical value beyond the criteria of the World Health Organization fourth edition (WHO4; normal ≥14%).

Design

Retrospective study.

Setting

Tertiary hospital.

Patients

Men without known azoospermia who had semen analysis (SA) collected over a 10-year period of time.

Interventions

Morphology classification under Kruger WHO5 strict criteria and WHO4 criteria.

Main Outcome Measures

Correlation between the WHO5 and WHO4 morphological classifications.

Results

A total of 4,510 SAs were identified during the study period. Of these, both Kruger WHO5 and WHO4 morphologies were included in 932 SAs (20.7%) from a total of 691 men. The median age of the men was 37 years (interquartile range, 32.0-43.8 years). The mean (±SD) semen volume, sperm concentration, and motility were 2.6 ± 1.4 mL, 50.0 ± 35.6 × 10⁶/mL, and 53.1% ± 18.6%, respectively. The correlation between the WHO4 and WHO5 morphology assessments was high (Spearman correlation coefficient = 0.94). Only 545 (58.5%) of 932 SAs had abnormal Kruger WHO5 morphology, of which 543 (99.6%) of 545 also had abnormal morphology by the WHO4 criteria.

Conclusions

The Kruger WHO5 and WHO4 morphologic criteria correlate closely. Only two men (0.4%) with an abnormal Kruger morphology had normal WHO4 morphology. Given the limited predictive value of sperm morphology, the additional cost and effort of Kruger criteria may not be warranted in lieu of, or in addition to, the WHO4 classification.

One potential biomarker for teratozoospermia identified by in-depth integrative analysis of multiple microarray data

Teratozoospermia is a common category of male infertility and with the increase in clinical patients and the increasing sophistication of assisted reproductive technology, there is an urgent need for an accurate semen diagnostic biomarker to accomplish rapid diagnosis of patients with teratozoospermia and accurately assess the success rate of assisted reproductive technologies. In this study, we performed gene differential expression analysis on two publicly available DNA microarray datasets (GSE6872 and GSE6967), followed by GSEA analysis to parse their enriched KEGG pathways, and WGCNA analysis to obtain the most highly correlated modules. Subsequent in-depth comparative analysis of the modules screened into the two datasets resulted in a gene set containing the identical expression trend, and then the differentially expressed genes in the set were screened using the corresponding criteria. Finally, three differentially expressed genes common to both datasets were selected. In addition, we validated the expression changes of this gene using another dataset (GSE6968) and in vitro experiments, and only screened one potential semen biomarker gene whose expression trend was identical to those in other datasets, which will also provide an important theoretical basis for the diagnosis and treatment of teratozoospermia.

Genetic basis of acephalic spermatozoa syndrome, and intracytoplasmic sperm injection outcomes in infertile men: a systematic scoping review

PURPOSE

Acephalic spermatozoa syndrome (ASS) is known as a severe type of teratozoospermia, defined as semen composed of mostly headless spermatozoa that affect male fertility. In this regard, this systematic review aimed to discuss gene variants associated with acephalic spermatozoa phenotype as well as the clinical outcomes of intracytoplasmic sperm injection (ICSI) treatment for the acephalic spermatozoa-associated male infertility.

METHODS

A systematic search was performed on PubMed, Embase, Scopus, and Ovid databases until May 17, 2020. This systematic scoping review was reported in terms of the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) statement.

RESULTS

Twenty articles were included in this systematic review. Whole-exome and Sanger sequencing have helped in the identification of variants in SUN5, PMFBP1, BRDT, TSGA10, DNAH6, HOOK1, and CEP112 genes as possible causes of this phenotype in humans. The results of the ICSI are conflicting due to both positive and negative reports of ICSI outcomes.

CONCLUSION

ASS has a genetic origin, and several genetic alterations related to the pathogenesis of this anomaly have been recently identified. Notably, only SUN5 and PMFBP1 mutations are well-known to be implicated in ASS. Accordingly, more functional studies are needed to confirm the pathogenicity of other variants. ICSI could provide a promising treatment for acephalic spermatozoa-associated male infertility. Besides the importance of sperm head-tail junction integrity, some other factors, whether within the sperm cell or female factors, may be involved in the ICSI outcome.

Assessment of Atg7 and LC3II/LC3, as The Markers of Autophagy, in Sperm of Infertile Men with Globozoospermia: A Case-Control Study

Objective

Assessment of relationship between LC3II/LC3 and Autophagy-related 7 (Atg7) proteins, as markers of autophagy, as well as evaluating the sperm parameters and DNA fragmentation in spermatozoa of infertile men with globozoospermia.

Materials and Methods

In this case-control study, 10 semen samples from infertile men with globozoospermia and 10 fertile individuals were collected, and the sperm parameters, sperm DNA fragmentation, and main autophagy markers (Atg7 and LC3II/LC3) were assessed according to World Health Organization (WHO) criteria, TUNEL assay, and western blot technique, respectively.

Results

The mean of sperm concentration and motility were significantly lower, while the percentage of abnormal spermatozoa and DNA fragmentation were significantly higher in infertile men with globozoospermia compared to fertile individuals (P<0.01). Unlike the relative expression of LC3II/LC3 that did not significantly differ between the two groups, the relative expression of ATG7 was significantly higher in infertile men with globozoospermia compared to fertile individuals (P<0.05). There was a significantly negative correlation between the sperm concentration (r=-0.679; P=0.005) and motility (r=-0.64; P=0.01) with the expression of ATG7, while a significantly positive association was founf between the percentage of DNA fragmentation and expression of ATG7 (0.841; P =0.018).

Conclusion

The increased expression of ATG7 and unaltered expression of LC3II/LC3 may indicate that the autophagy pathway is initiated but not completely executed in spermatozoa of individuals with globozoospermia. A significant correlation of ATG7 expression with increased sperm DNA fragmentation, reduced sperm concentration, and sperm motility may associate with the activation of a compensatory mechanism for promoting deficient spermatozoa to undergo cell death by the autophagy pathway. Therfore, this pathway could act as a double-edged sword that, at the physiological level, is involved in acrosome biogenesis, while, at the pathological level, such as globozoospermia, could act as a compensatory mechanism.

Influence of sperm morphology on pregnancy outcome and offspring in in vitro fertilization and intracytoplasmic sperm injection: a matched case-control study

Sperm morphology was once believed as one of the most predictive indicators of pregnancy outcome in assisted reproductive technology (ART). However, the impact of teratozoospermia on in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes and its offspring remains inconclusive. In order to evaluate the influence of teratozoospermia on pregnancy outcome and newborn status after IVF and ICSI, a retrospective study was conducted. This was a matched case-control study that included 2202 IVF cycles and 2574 ICSI cycles and was conducted at the Reproductive and Genetic Hospital of CITIC-Xiangya in Changsha, China, from June 2013 to June 2018. Patients were divided into two groups based on sperm morphology: teratozoospermia and normal sperm group. The pregnancy outcome and newborn outcome were analyzed. The results indicated that couples with teratozoospermia had a significantly lower optimal embryo rate compared to those with normal sperm morphology in IVF (P = 0.007), while there were no statistically significant differences between the two groups in terms of the fertilization rate, cleavage rate, implantation rate, and pregnancy rate (all P > 0.05). Additionally, teratozoospermia was associated with lower infant birth weight in multiple births after IVF. With regard to ICSI, there was no significant difference in both pregnancy outcome and newborn outcome between the teratozoospermia and normal groups (both P > 0.05). Furthermore, no increase in the risk of birth defects occurred in the teratozoospermia group after IVF/ICSI. Consequently, we believe that teratozoospermia has limited predictive value for pregnancy outcomes in IVF/ICSI, and has little impact on the resulting offspring if multiple pregnancy is avoided.

The hamster egg penetration test may decrease intracytoplasmic sperm injection utilization while maintaining high conventional fertilization rates

This was a cohort study of in vitro fertilization (IVF) subjects at the University of Utah, Salt Lake City (UT, USA) utilizing partner sperm. Cycles where both the hamster egg penetration test (HEPT) and semen analysis were performed within 2 years prior to IVF cycles were stratified into four groups based on a normal or an abnormal HEPT and morphology. The mean conventional and intracytoplasmic sperm injection (ICSI) fertilization rates were calculated in each group. We performed a univariate analysis on the primary outcome comparing clinically interesting subjects. We performed a cost-effectiveness analysis of a policy of HEPT versus universal ICSI in couples with an abnormal morphology. Among patients with a normal HEPT, there was no difference in the mean conventional fertilization rates between those with a normal and an abnormal morphology. There was no difference in the mean conventional fertilization rates between subjects with a normal morphology without a hamster test and those with a normal HEPT without a morphology assessment. In 1000 simulated cycles with an abnormal morphology, a policy of HEPT was cost saving compared to universal ICSI, yet produced similar fertilization rates. The HEPT is similar to the World Health Organization edition 5 (WHO-5) morphology in predicting successful conventional fertilization while allowing decreased utilization of ICSI. A policy of HEPT for males with abnormal morphology saves cost in selecting couples for a fertilization method.

Does omitting teratospermia as a selection criterion for ICSI change pregnancy rates?

PURPOSE

There is controversy whether teratospermia is associated with poorer IVF outcomes and if ICSI may overcome this deficit. The debate likely lies in study heterogeneity, poor adjustment for confounders, and inter-observer variation in sperm morphology assessment. Given the current literature, a shift in practice was implemented at our center in February 2017, whereby teratospermia was no longer a criterion for ICSI. We hypothesized that, despite decreasing ICSI rates, we would see no change in ART outcomes.

METHODS

A retrospective study was performed including 1821 couples undergoing IVF/ICSI at a single center from January 2016 to December 2018, divided into cohorts before and after the practice change. The primary outcome of clinical pregnancy and secondary outcomes of fertilization, fertilization failure, good quality blastocyst formation, embryo utilization, positive hCG, and miscarriage rates was compared, adjusting for potential confounders. Subgroup analysis was performed evaluating teratospermia as the only reason for a male factor infertility diagnosis.

RESULTS

Despite a decrease in ICSI rate of 30.3%, we found no significant difference in clinical intrauterine pregnancy rate, with an adjusted relative risk of 0.93 (0.81, 1.07, P = 0.3008). There were no significant differences in other secondary outcomes after multivariate adjustment. Subgroup analysis for those with male factor infertility due to teratospermia showed no difference in outcomes.

CONCLUSION

This study concurs with the recent data suggesting that employing ICSI solely for teratospermia is unnecessary. This may allow clinics to decrease ICSI rates without sacrificing success rates, leading to lower cost and risk associated with treatment.

Evaluation, Treatment, and Insurance Coverage for Couples With Male Factor Infertility in the US: A Cross-Sectional Analysis of Survey Data

OBJECTIVE

To characterize the evaluation, treatment, and insurance coverage among couples with male factor infertility in the United States.

MATERIALS AND METHODS

A cohort of 969 couples undergoing fertility treatment with a diagnosis of male factor infertility were identified from an online survey. The proportion of men that were seen/not seen by a male were compared. Insurance coverage related to male factor was also assessed.

RESULTS

Overall, 98.0% of the men reported at least one abnormal semen parameter. Of these, 72.0% were referred to a male fertility specialist with the majority being referred by the gynecologist of their female partner. As part of the male evaluation, 72.2% had blood hormone testing. Of the 248 men who were not recommended to see a male fertility specialist, 96.0% had an abnormal semen analysis including 7.6% who had azoospermia. Referral to a male fertility specialist was largely driven by severity of male factor infertility rather than socioeconomic status. Insurance coverage related to male factor infertility was poor with low coverage for sperm extractions (72.9% reported 0-25% coverage) and sperm freezing (83.7% reported 0-25% coverage).

CONCLUSION

Although this cohort includes couples with abnormal semen parameters, 28% of the men were not evaluated by a male fertility specialist. In addition, insurance coverage for services related to male factor was low. These findings may be of concern as insufficient evaluation and coverage of the infertile man could lead to missed opportunities for identifying reversible causes of infertility/medical comorbidities and places an unfair burden on the female partner.

When to do intracytoplasmic sperm injection: a prospective comparison

PURPOSE

The purpose of the study was to assess the fertilization rate and embryo development in sibling human oocytes after split insemination in patients with and without isolated teratozoospermia.

METHODS

A prospective cohort study at a university affiliated reproduction center was performed. Hundred and three patients during the time periods 01-2013 to 12-2015 had split insemination ordered for their first IVF cycle. The primary outcome measured was fertilization rate. Secondary outcomes were the number and quality of embryos.

RESULTS

Mature oocytes at the time of collection were assigned as follows: 558 to IVF and 556 to ICSI. An additional 48 immature oocytes matured while awaiting spontaneous fertilization with IVF for a total of 606 in that group. The study group of normal strict sperm morphology ≤ 4 included 61 patients, and the control group included 42 patients with normal strict sperm morphology > 4. ICSI was statistically favored over IVF only in cases with normal strict sperm morphology ≤ 4%. There was a higher fertilization rate in ICSI compared to IVF (74.4% vs. 38%, p < 0.0001), a higher number of day 2 (4 ± 3.4 vs. 2.4 ± 2.7, p < 0.0001), day 3 (4 ± 3.4 vs. 2.2 ± 2.7, p < 0.0001) and day 5 embryos (2.2 ± 2.6 vs. 1.2 ± 2, p = 0.001), and they were of better quality; however, it did not reach significance (p = 0.062). A similar advantage for ICSI was seen in a subgroup of unexplained infertility with normal strict sperm morphology > 4%.

CONCLUSIONS

In conclusion, in couples with normal strict sperm morphology ≤ 4%, there is an advantage of ICSI over IVF in terms of fertilization rate, quantity and quality of cleavage stage embryos and blastocysts. Based on the results, ICSI seems reasonable as a first-line treatment in patients with normal strict sperm morphology ≤ 4%, as well as in patients with unexplained infertility.

Intracytoplasmic sperm injection for male infertility and consequences for offspring

Intracytoplasmic sperm injection (ICSI) has become the most commonly used method of fertilization in assisted reproductive technology. The primary reasons for its popularity stem from its effectiveness, the standardization of the procedure, which means that it can easily be incorporated into the routine practice of fertility centres worldwide, and the fact that it can be used to treat virtually all forms of infertility. ICSI is the clear method of choice for overcoming untreatable severe male factor infertility, but its (over)use in other male and non-male factor infertility scenarios is not evidence-based. Despite all efforts to increase ICSI efficacy and safety through the application of advanced sperm retrieval and cryopreservation techniques, as well as methods for selecting sperm with better chromatin integrity, the overall pregnancy rates from infertile men remain suboptimal. Treating the underlying male infertility factor before ICSI seems to be a promising way to improve ICSI outcomes, but data remain limited. Information regarding the health of ICSI offspring has accumulated over the past 25 years, and there are reasons for concern as risks of congenital malformations, epigenetic disorders, chromosomal abnormalities, subfertility, cancer, delayed psychological and neurological development, and impaired cardiometabolic profile have been observed to be greater in infants born as a result of ICSI than in naturally conceived children. However, as subfertility probably influences the risk estimates, it remains to be determined to what extent the observed adverse outcomes are related to parental factors or associated with ICSI.

Sperm Morphology: History, Challenges, and Impact on Natural and Assisted Fertility

PURPOSE OF REVIEW

The classification of morphologically normal sperm has been progressively redefined. Concurrently, our understanding of the significance of sperm morphology in relation to male factor infertility has evolved. In this review, we will discuss the evolution of sperm morphology assessment and factors that contribute to its measurement variability. We will examine the impact of sperm morphology on natural pregnancy, IUI, IVF, and ICSI outcomes.

RECENT FINDINGS

There is a lack of consensus on sperm morphology classification, technique, and inter-observer grading variability. Current evidence suggests sperm morphology has low predictive value for pregnancy success, for both natural and assisted reproduction. Additionally, the threshold for what is considered an adequate percentage of morphologically normal sperm has changed over time. These variables have called into question the relevance of this variable in predicting fertility outcomes. Our understanding of the impact of sperm morphology on reproductive outcomes continues to evolve and seems to play less of a role than initially thought.

Role of Oxidative Stress in Male Infertility: An Updated Review

Current evidence links oxidative stress (OS) to male infertility, reduced sperm motility, sperm DNA damage and increased risk of recurrent abortions and genetic diseases. A review of PubMed, Medline, Google Scholar, and Cochrane review databases of published articles from years 2000–2018 was performed focusing on physiological and pathological consequences of reactive oxygen species (ROS), sperm DNA damage, OS tests, and the association between OS and male infertility, pregnancy and assisted reproductive techniques outcomes. Generation of ROS is essential for reproductive function, but OS is detrimental to fertility, pregnancy, and genetic status of the newborns. Further, there is a lack of consensus on selecting OS test, type, and duration of antioxidants treatment as well as on the target patients group. Developing advanced diagnostic and therapeutic options for OS is essential to improve fertility potential and limit genetic diseases transmitted to offspring.

Role of Sperm Morphology in Deciding Between Various Assisted Reproduction Technologies

Sperm morphology has long been used as a clinical tool in the assessment of men with infertility. In the past, high percentages of abnormal sperm have been associated with lower pregnancy rates. However, significant intra- and interlaboratory variation has been found for sperm morphology assessment and several recent meta-analyses have demonstrated that sperm morphology is no longer predictive of lower pregnancy rates when using assisted reproduction technology (ART). As the validity of the test and the predictive nature of sperm morphology are no longer as robust as before, clinicians should not rely on percentage thresholds for normal sperm when deciding on which ART to opt for. Instead, clinicians should base ART decisions on other reproductive factors.

Knowledge gaps in male infertility: a reproductive endocrinology and infertility perspective

Reproductive research has moved forward at a remarkable pace. Some of these advances are the result of a separation between male and female specialties, allowing focused study in specific areas of the field. However, the different training programs between male and female fertility specialists has created an environment in which some discoveries are not put in the greater context of clinical care. At times, interventions have been measured against surrogate markers of outcome that may not impact the most meaningful outcome for patients—the delivery of a healthy neonate. For example, medical and surgical interventions that use changes in semen parameters may have a limited impact on the likelihood of achieving a live birth due to the limitations inherent in the semen analysis for predicting outcomes. Other commonly used tests, such as sperm DNA fragmentation assays provide promising biological plausibility to account for subfertility of some male partners. However, until well defined thresholds for predicting outcomes in different treatment scenarios are available, changes in sperm DNA fragmentation testing is not an adequate outcome for measuring the utility of interventions. The biggest limitation for these tests remains their analysis of bulk semen. Tests allowing interrogation of the reproductive competence of a given sperm, while allowing that sperm to be used in assisted reproductive technology procedures remain elusive. Progress toward reaching this end (whether by hyaluronic acid binding, IMSI, or Ramen spectroscopy) is underway, but much remains to be learned. Achieving testing and capture of individual sperm would better facilitate studies that measure the most meaningful outcome for patients and providers—the delivery of a healthy baby.

The effect of human sperm chromatin maturity on ICSI outcomes

Because sperm chromatin may play a key role in reproductive success, we verify the associations between sperm chromatin abnormalities, embryo development and the ability to achieve pregnancy. The evaluation of sperm chromatin maturity using aniline blue (AB), chromomycin A3 (CMA3) and toluidine blue (TB) staining were carried out in group of males from infertile couples that underwent ICSI. Low levels of sperm chromatin abnormalities (< 16%) were found in most subjects (> 50%). A higher percentage of TB-positive sperm cells were discovered in the men from couples who achieved ≤ 50% fertilized oocytes compared to men who achieved > 50%. No significant differences were discovered by the applied tests between the men from couples who achieved ≤ 50% and those who achieved > 50% high-quality embryos on the 3rd or 5th day after fertilization, nor between the men from couples who achieved pregnancy and those who failed. The sperm chromatin maturity did not correlate with the ICSI results. However, the ROC analysis revealed a significant predictive value of TB-positive spermatozoa only for fertilization. Therefore, the TB assay can be considered as a useful test for the prediction of fertilization. Our findings suggest that the level of sperm chromatin abnormalities of the examined men was not clinically significant. No found associations between sperm chromatin maturity and embryo development and the ability to achieve pregnancy. We could not exclude the effects of the repairing processes in the fertilized oocyte. The use of complementary tests that verify the status of the sperm chromatin seems justified.

Oxidation-reduction potential and sperm DNA fragmentation, and their associations with sperm morphological anomalies amongst fertile and infertile men

Objective

To assess seminal oxidation–reduction potential (ORP) and sperm DNA fragmentation (SDF) in male infertility and their relationships with sperm morphology in fertile and infertile men.

Patients and methods

Prospective case-control study comparing the findings of infertile men (n = 1168) to those of men with confirmed fertility (n = 100) regarding demographics and semen characteristics (conventional and advanced semen tests). Spearman rank correlation assessed the correlation between ORP, SDF, and different morphological indices. Means of ORP and SDF were assessed in variable levels of normal sperm morphology amongst all participants.

Results

Infertile patients had a significantly lower mean sperm count (32.7 vs 58.7 × 10⁶ sperm/mL), total motility (50.1% vs 60.4%), and normal morphology (5.7% vs 9.9%). Conversely, infertile patients had significantly higher mean head defects (54% vs 48%), and higher ORP and SDF values than fertile controls. ORP and SDF showed significant positive correlations and significant negative correlations with sperm head defects and normal morphology in infertile patients, respectively. ORP and SDF were significantly inversely associated with the level of normal sperm morphology. Using receiver operating characteristic curve analysis, ORP and SDF threshold values of 1.73 mV/10⁶ sperm/mL and 25.5%, respectively, were associated with 76% and 56% sensitivity and 72% and 72.2% specificity, respectively, in differentiating <4% from ≥4% normal morphology.

Conclusion

A direct inverse relationship exists between seminal ORP and SDF with various levels of normal sperm morphology. Using ORP and SDF measures in conjunction with standard semen morphology analysis could validate the result of the fertility status of patients.

CASA in the medical laboratory: CASA in diagnostic andrology and assisted conception

CASA has been used in reproductive medicine and pathology laboratories for over 25 years, yet the ‘fertility industry’ generally remains sceptical and has avoided automation, despite clear weaknesses in manual semen analysis. Early implementers had difficulty in validating CASA-Mot instruments against recommended manual methods (haemocytometer) due to the interference of seminal debris and non-sperm cells, which also affects the accuracy of grading motility. Both the inability to provide accurate sperm counts and a lack of consensus as to the value of sperm kinematic parameters appear to have continued to have a negative effect on CASA-Mot’s reputation. One positive interpretation from earlier work is that at least one or more measures of sperm velocity adds clinical value to the semen analysis, and these are clearly more objective than any manual motility analysis. Moreover, recent CASA-Mot systems offer simple solutions to earlier problems in eliminating artefacts and have been successfully validated for sperm concentration; as a result, they should be viewed with more confidence in relation to motility grading. Sperm morphology and DNA testing both require an evidence-based consensus and a well-validated (reliable, reproducible) assay to be developed before automation of either can be of real clinical benefit.

Uncertainty of measurement and clinical value of semen analysis: has standardisation through professional guidelines helped or hindered progress?

This article suggests that diagnostic semen analysis has no more clinical value today than it had 25-30 years ago, and both the confusion surrounding its evidence base (in terms of relationship with conception) and the low level of confidence in the clinical setting is attributable to an associated high level of 'uncertainty'. Consideration of the concept of measurement uncertainty is mandatory for medical laboratories applying for the ISO15189 standard. It is evident that the entire semen analysis process is prone to error every step from specimen collection to the reporting of results and serves to compound uncertainty associated with diagnosis or prognosis. Perceived adherence to published guidelines for the assessment of sperm concentration, motility and morphology does not guarantee a reliable and reproducible test result. Moreover, the high level of uncertainty associated with manual sperm motility and morphology can be attributed to subjectivity and lack a traceable standard. This article describes where and why uncertainty exists and suggests that semen analysis will continue to be of limited value until it is more adequately considered and addressed. Although professional guidelines for good practice have provided the foundations for testing procedures for many years, the risk in following rather prescriptive guidance to the letter is that unless they are based on an overwhelmingly firm evidence base, the quality of semen analysis will remain poor and the progress towards the development of more innovative methods for investigating male infertility will be slow.

Chromatin Protamination and Catsper Expression in Spermatozoa Predict Clinical Outcomes after Assisted Reproduction Programs

Identification of parameters predicting assisted reproductive technologies (ARTs) success is a major goal of research in reproduction. Quality of gametes is essential to achieve good quality embryos and increase the success of ARTs. We evaluated two sperm parameters, chromatin maturity and expression of the sperm specific calcium channel CATSPER, in relation to ART outcomes in 206 couples undergoing ARTs. Chromatin maturity was evaluated by Chromomycin A3 (CMA3) for protamination and Aniline Blue (AB) for histone persistence and CATSPER expression by a flow cytometric method. CMA3 positivity and CATSPER expression significantly predicted the attainment of good quality embryos with an OR of 6.6 and 14.3 respectively, whereas AB staining was correlated with fertilization rate. In the subgroup of couples with women ≤35 years, CATSPER also predicted achievement of clinical pregnancy (OR = 4.4). Including CMA3, CATSPER and other parameters affecting ART outcomes (female age, female factor and number of MII oocytes), a model that resulted able to predict good embryo quality with high accuracy was developed. CMA3 staining and CATSPER expression may be considered two applicable tools to predict ART success and useful for couple counseling. This is the first study demonstrating a role of CATSPER expression in embryo development after ARTs programs.

Deficiency in Sperm-Egg Protein Interaction as a Major Cause of Fertilization Failure

Complete elucidation of fertilization process at molecular level is one of the unresolved challenges in sexual reproduction studies, and understanding the molecular mechanism is crucial in overcoming difficulties in infertility and unsuccessful in vitro fertilization. Sperm-oocyte interaction is one of the most remarkable events in fertilization process, and deficiency in protein-protein interactions which mediate this interaction is a major cause of unexplained infertility. Due to detection of how the various defects of sperm-oocyte interaction can affect fertilization failure, different experimental methods have been applied. This review summarizes the current understanding of sperm-egg interaction mechanism during fertilization and also accumulates the different types of sperm-egg interaction abnormalities and their association with infertility. Several detection approaches regarding sperm-egg protein interactions and the associated defects are reviewed in this paper.

Major regulatory mechanisms involved in sperm motility

The genetic bases and molecular mechanisms involved in the assembly and function of the flagellum components as well as in the regulation of the flagellar movement are not fully understood, especially in humans. There are several causes for sperm immotility, of which some can be avoided and corrected, whereas other are related to genetic defects and deserve full investigation to give a diagnosis to patients. This review was performed after an extensive literature search on the online databases PubMed, ScienceDirect, and Web of Science. Here, we review the involvement of regulatory pathways responsible for sperm motility, indicating possible causes for sperm immotility. These included the calcium pathway, the cAMP-dependent protein kinase pathway, the importance of kinases and phosphatases, the function of reactive oxygen species, and how the regulation of cell volume and osmolarity are also fundamental components. We then discuss main gene defects associated with specific morphological abnormalities. Finally, we slightly discuss some preventive and treatments approaches to avoid development of conditions that are associated with unspecified sperm immotility. We believe that in the near future, with the development of more powerful techniques, the genetic causes of sperm immotility and the regulatory mechanisms of sperm motility will be better understand, thus enabling to perform a full diagnosis and uncover new therapies.

Men with a complete absence of normal sperm morphology exhibit high rates of success without assisted reproduction

In couples with infertility, abnormal strict morphology of 0% normal forms (NF) is a criterion to proceed rapidly to in vitro fertilization (IVF). Since no data currently exist, we investigated the outcomes for men with 0% NF to determine reproductive success without the use of assisted reproductive technologies (ART). A cohort of 24 men with 0% NF were identified (2010-2013) with 27 randomly selected men with ≥4% NF as controls. Patient charts were reviewed with men contacted and administered an Institutional Review Board (IRB)-approved telephone questionnaire to ascertain outcomes. After a median follow-up time of 2.5 years, 29.2% of men with 0% NF did not require ART for their first pregnancy (controls = 55.6%, P ≤ 0.05). When all pregnancies were analyzed together, men with 0% NF achieved twenty pregnancies of which 75% did not require IVF (controls = thirty pregnancies; 76.7% did not require IVF). The average age of men and female partners was similar between men with 0% NF and ≥4% NF. All men had normal follicle-stimulating hormone (FSH), testosterone, prolactin, sex hormone-binding globulin (SHBG), and estradiol. Although, global semen parameters were worse in men with 0% NF, when a first pregnancy was a natural conception (NC), 100% of men with 0% NF (n = 7/7) and 37.5% of controls (n = 3/8) went on to have a subsequent pregnancy via NC. Men with 0% NF conceived without IVF in 29.2% of cases compared to 55.6% of controls. Strict morphology should not be used to predict fertilization, pregnancy, or live birth potential. In men with 0% NF, alternative modalities should be considered before immediate IVF.

Sperm quality and paternal age: effect on blastocyst formation and pregnancy rates

BACKGROUND

Several studies suggest a decrease in sperm quality in men in the last decades. Therefore, the aim of this work was to assess the influence of male factors (sperm quality and paternal age) on the outcomes of conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

METHODS

This retrospective study included all couples who underwent IVF or ICSI at Montpellier University Hospital, France, between 1 January 2010 and 31 December 2015. Exclusion criteria were cycles using surgically retrieved sperm or frozen sperm, with pre-implantation genetic diagnosis or using frozen oocytes. The primary outcomes were the blastulation rate (number of blastocysts obtained at day 5 or day 6/number of embryos in prolonged culture at day 3) and the clinical pregnancy rate. The secondary outcomes were the fertilization and early miscarriage rates.

RESULTS

In total, 859 IVF and 1632 ICSI cycles were included in this study. The fertilization rate after ICSI was affected by oligospermia. Moreover, in ICSI, severe oligospermia (lower than 0.2 million/ml) led to a reduction of the blastulation rate. Reduced rapid progressive motility affected particularly IVF, with a decrease of the fertilization rate and number of embryos at day 2 when progressive motility was lower than 32%. Paternal age also had a negative effect. Although it was difficult to eliminate the bias linked to the woman's age, pregnancy rate was reduced in IVF and ICSI when the father was older than 51 and the mother older than 37 years.

CONCLUSIONS

These results allow adjusting our strategies of fertilization technique and embryo transfer. In the case of severe oligospermia, transfer should be carried out at the cleaved embryo stage (day 2-3) due to the very low blastulation rate. When the man is older than 51 years, couples should be aware of the reduced success rate, especially if the woman is older than 37 years. Finally, promising research avenues should be explored, such as the quantification of free sperm DNA, to optimize the selection of male gametes.

Role of Abnormal Sperm Morphology in Predicting Pregnancy Outcomes

The evaluation of strict morphology for predicting successful pregnancy has been controversial, nevertheless remains an essential component of semen analysis. Patients with teratozoospermia (abnormal strict morphology) have traditionally been counseled to undergo assisted reproduction. However, recent studies suggest that patients with abnormal sperm morphology alone should not be precluded from attempting natural conception before undergoing assisted reproduction. The goal of this review is to provide an update on the evaluation of sperm morphology for prognosis in assisted reproductive techniques such as intrauterine insemination and in vitro fertilization with or without intracytoplasmic sperm injection. Additionally, we propose a logical approach to the evaluation of a patient with teratozoospermia seeking fertility treatment.

Effect of normal sperm morphology rate (NSMR) on clinical outcomes and fertilization methods selection in the ultra-short-term GnRH-a protocol

PURPOSE

To investigate whether intracytoplasmic sperm injection (ICSI) can improve the clinical outcomes of the male patients with teratozoospermia in the ultra-short term GnRH-a protocol.

METHODS

Based on different normal sperm morphology rate (NSMR), the patients were divided into three groups as follows: NSMR = 0% group, 1% ≤NSMR <4% group and NSMR ≥4% group. Each group was compared with two fertilization type of in-vitro fertilization (IVF) and ICSI separately. Main outcomes compared were normal fertilization, high-quality embryo, transferrable embryo, implantation, pregnancy and abortion rate.

RESULTS

We observed that the total clinical pregnancy rate in single cleavage-stage embryo transfer (SET) group was significantly lower compared with double cleavage-stage embryo transfer (DET) group (23.87% versus 40.08%; p < 0.001). There was no significant difference in the aspects of female age, endometrial thickness, infertility duration and the number of retrieved oocytes among three groups (p > 0.05). The normal fertilization, high-quality embryo, transferrable embryo, implantation, pregnancy and abortion rate of IVF and ICSI showed no significant difference among three groups (p > 0.05).

CONCLUSION

ICSI cannot improve clinical outcomes of the patients with teratozoospermia in the ultra-short term GnRH-a protocol.

Outcomes of Intracytoplasmic Sperm Injection Cycles for Complete Teratozoospermia: A Case-Control Study Using Paired Sibling Oocytes

OBJECTIVE

To investigate the outcomes of intracytoplasmic sperm injection (ICSI) cycles where sibling oocytes from a single donor were split between two recipients based on strict sperm morphology.

METHODS

Retrospective cohort study. All ICSI cycles had one donor's oocytes split between two recipients in a 1 : 1 ratio based on strict sperm morphology, that is, one male partner had morphology of 0% and the other had morphology of >1%. Fertilization, positive hCG, clinical pregnancy, spontaneous miscarriage, and live birth rates of the aforementioned groups were compared.

RESULTS

The baseline characteristics of the two groups (n = 103), including semen parameters of the male partners, were comparable. There was no difference in the fertilization rates when comparing the 0% group to the >1% group (78.7% versus 81.6%; P = 0.66). The overall positive hCG, clinical pregnancy, spontaneous miscarriage, and live birth rates for the 0% group were 61.2%, 49.5%, 10.7%, and 38.8%, respectively. The corresponding rates in the >1% group were positive hCG (63.1%), clinical pregnancy (55.3%), spontaneous miscarriage (7.77%), and live birth (46.6%).

CONCLUSIONS

The fertilization and pregnancy outcomes of ICSI cycles for strict sperm morphology of 0% versus morphology of >1% are equivalent. These results can provide reassurance to couples undergoing ICSI for severe teratospermia.

Comparison of conventional in vitro fertilisation and intracytoplasmic sperm injection outcomes in patients with moderate oligoasthenozoospermia

The method of choice for assisted reproductive technology treatment in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) is usually based on the evaluation of male infertility factors. Decisions for couples with moderate oligoasthenozoospermia (OA) are often empirical because uniform treatment criteria are lacking. This study aimed to evaluate the effect of patients with moderate OA treated with conventional IVF and ICSI. A total of 199 couples with moderate OA undergoing their first IVF/ICSI cycle were included in the study. The patients were divided into two groups according to the type of insemination: conventional IVF group (n = 97) and ICSI group (n = 102). All patients were randomised to be inseminated either by conventional IVF or ICSI. The fertilisation rate, embryo quality, implantation rate and clinical pregnancy rate were examined. No differences in the fertilisation, implantation and pregnancy rates were observed between conventional IVF and ICSI groups (P > 0.05). However, the number of good-quality embryos was significantly higher in the ICSI group than in the IVF group (P < 0.05). Couples with moderate OA did not influence on the overall clinical outcomes between IVF and ICSI treatments, and a negative influence by ICSI on blastocyst development was not confirmed.

Probing the effect of human normal sperm morphology rate on cycle outcomes and assisted reproductive methods selection

Sperm morphology is the best predictor of fertilization potential, and the critical predictive information for supporting assisted reproductive methods selection. Given its important predictive value and the declining reality of semen quality in recent years, the threshold of normal sperm morphology rate (NSMR) is being constantly corrected and controversial, from the 4^th edition (14%) to the 5^th version (4%). We retrospectively analyzed 4756 cases of infertility patients treated with conventional-IVF(c-IVF) or ICSI, which were divided into three groups according to NSMR: ≥14%, 4%–14% and <4%. Here, we demonstrate that, with decrease in NSMR(≥14%, 4%–14%, <4%), in the c-IVF group, the rate of fertilization, normal fertilization, high-quality embryo, multi-pregnancy and birth weight of twins gradually decreased significantly (P<0.05), while the miscarriage rate was significantly increased (p<0.01) and implantation rate, clinical pregnancy rate, ectopic pregnancy rate, preterm birth rate, live birth rate, sex ratio, and birth weight(Singleton) showed no significant change. In the ICSI group, with decrease in NSMR (≥14%, 4%–14%, <4%), high-quality embryo rate, multi-pregnancy rate and birth weight of twins were gradually decreased significantly (p<0.05), while other parameters had no significant difference. Considering the clinical assisted methods selection, in the NFMR ≥14% group, normal fertilization rate of c-IVF was significantly higher than the ICSI group (P<0.05), in the 4%–14% group, birth weight (twins) of c-IVF were significantly higher than the ICSI group, in the <4% group, miscarriage of IVF was significantly higher than the ICSI group. Therefore, we conclude that NSMR is positively related to embryo reproductive potential, and when NSMR<4% (5^th edition), ICSI should be considered first, while the NSMR≥4%, c-IVF assisted reproduction might be preferred.