Effects of supplement therapy on sperm parameters, protamine content and acrosomal integrity of varicocelectomized subjects

Zinc as a Possible Critical Element to Prevent Harmful Effects of COVID-19 on Testicular Function: a Narrative Review

Research into innovative non-pharmacological therapeutic routes via the utilization of natural elements like zinc (Zn) has been motivated by the discovery of new severe acute respiratory syndrome-related coronavirus 2 (SARS-COV2) variants and the ineffectiveness of certain vaccination treatments during COVID-19 pandemic. In addition, research on SARS-COV-2's viral cellular entry and infection mechanism has shown that it may seriously harm reproductive system cells and impair testicular function in young men and adolescents, which may lead to male infertility over time. In this context, we conducted a narrative review to give an overview of the data pertaining to Zn's critical role in testicular tissue, the therapeutic use of such micronutrients to enhance male fertility, as well as in the potential mitigation of COVID-19, with the ultimate goal of elucidating the hypothesis of the potential use of Zn supplements to prevent the possible harmful effects of SARS-COV2 infection on testis physiological function, and subsequently, on male fertility.

Add-on effects of oral tocopherol supplementation to surgical varicocelectomy on the outcome of assisted reproductive technology: a single-center pilot study report

Introduction

Varicocelectomy is well known to improve the pregnancy outcome of patients with clinical varicoceles in assisted reproductive technologies as well as spontaneous conception. Therefore, this study aimed to evaluate the additional effects of oral antioxidant therapy after varicocelectomy on the pregnancy outcome in the assisted reproductive technology setting.

Methods

This study was a retrospective cohort study. The subjects were couples among whom the male partner had undergone varicocelectomy and was scheduled for subsequent assisted reproductive technology. Pregnancy outcomes were followed retrospectively in 62 couples with male partners who received tocopherol (antioxidant group) and 37 couples who did not (control group). The tocopherol and control groups were assigned dependent on the decision of the physician in charge and the patient's request. The clinical pregnancy rates per couple and embryo transfer, time to pregnancy, and the number of cycles during transfer to pregnancy were evaluated.

Results

No significant differences were observed in the pregnancy rate per couple (antioxidant group 70.9% vs. control group 64.9%, P = 0.55) and per embryo transfer (50.4% vs. 39.6%, P = 0.22). Regarding the time to event analyzed by adjusted restricted mean survival time, the mean time to pregnancy was significantly shorter in the antioxidant (tocopherol) group (14.2 vs. 17.4 months, P = 0.025). No significant difference was observed in the embryo transfer cycle to pregnancy (mean embryo transfer cycles: 2.6 vs. 3.0, P = 0.238).

Conclusions

Additional oral tocopherol nicotinate as antioxidant therapy after varicocelectomy was shown to shorten the time to pregnancy. It is recommended that add-on effects be tested in more well-designed randomized controlled trials to examine whether it improves assisted reproductive outcomes.

Does Varicocele Repair Improve Conventional Semen Parameters? A Meta-Analytic Study of Before-After Data

PURPOSE

The purpose of this meta-analysis is to study the impact of varicocele repair in the largest cohort of infertile males with clinical varicocele by including all available studies, with no language restrictions, comparing intra-person conventional semen parameters before and after the repair of varicoceles.

MATERIALS AND METHODS

The meta-analysis was performed according to PRISMA-P and MOOSE guidelines. A systematic search was performed in Scopus, PubMed, Cochrane, and Embase databases. Eligible studies were selected according to the PICOS model (Population: infertile male patients with clinical varicocele; Intervention: varicocele repair; Comparison: intra-person before-after varicocele repair; Outcome: conventional semen parameters; Study type: randomized controlled trials [RCTs], observational and case-control studies).

RESULTS

Out of 1,632 screened abstracts, 351 articles (23 RCTs, 292 observational, and 36 case-control studies) were included in the quantitative analysis. The before-and-after analysis showed significant improvements in all semen parameters after varicocele repair (except sperm vitality); semen volume: standardized mean difference (SMD) 0.203, 95% CI: 0.129-0.278; p<0.001; I²=83.62%, Egger's p=0.3329; sperm concentration: SMD 1.590, 95% CI: 1.474-1.706; p<0.001; I²=97.86%, Egger's p<0.0001; total sperm count: SMD 1.824, 95% CI: 1.526-2.121; p<0.001; I²=97.88%, Egger's p=0.0063; total motile sperm count: SMD 1.643, 95% CI: 1.318-1.968; p<0.001; I²=98.65%, Egger's p=0.0003; progressive sperm motility: SMD 1.845, 95% CI: 1.537%-2.153%; p<0.001; I²=98.97%, Egger's p<0.0001; total sperm motility: SMD 1.613, 95% CI 1.467%-1.759%; p<0.001; l2=97.98%, Egger's p<0.001; sperm morphology: SMD 1.066, 95% CI 0.992%-1.211%; p<0.001; I²=97.87%, Egger's p=0.1864.

CONCLUSIONS

The current meta-analysis is the largest to date using paired analysis on varicocele patients. In the current meta-analysis, almost all conventional semen parameters improved significantly following varicocele repair in infertile patients with clinical varicocele.

The association of medications and supplements with human male reproductive health: a systematic review

Some medications used to treat comorbidities and conditions in reproductive-aged individuals could have a negative impact on fertility. This may occur through hormonal disruption, toxicity to germ cells and spermatozoa, functional impact on the sperm, teratogenicity potential, or ejaculatory abnormalities. Having knowledge of these potential interactions between medications and reproductive potential is important for clinicians to be aware of and guide the patient, along with their treating clinicians, to reproductively favorable alternatives when available. This review aims to summarize the state of the literature regarding medication interactions with human male reproduction using the Anatomical Therapeutic Chemical Classification System of medications.

Effects of the low-carb organic Mediterranean diet on testosterone levels and sperm DNA fragmentation

The causes of male infertility can vary. Lifestyles, environmental factors, stressful conditions, and socio-economic conditions are significant factors. Diet plays a crucial role in improving a man's reproductive capacity. The appropriate diet should be diverse and ensure the intake of all the necessary nutrients to enhance sperm quality. The Mediterranean diet, which includes high amounts of vegetables and fruits rich in detoxifying and antioxidant substances, as well as polyphenols, flavonoids, carotenoids, and microelements, especially when consumed with organic foods and a lower carbohydrate regimen, are the key aspects addressed in this study. The objective of this research was to modify the diets of 50 subfertile men by providing them with a specific nutritional plan. This plan included consuming 80% organic foods, introducing whole grains and low glycemic load options, eliminating refined carbohydrates, consuming green leafy vegetables and red fruits daily, reducing or eliminating dairy products, consuming primarily grass-fed meat and wild caught seafood, eliminating saturated fats in favor of healthy fats like olive oil, avocado, and nuts. After three months of adhering to the low-carb food plan, testosterone levels significantly increased, while sperm DNA fragmentation decreased in a subgroup of individuals who reduced their carbohydrate intake by 35%.

Synergetic effects of Mo2C sphere/SCN nanocatalysts interface for nanomolar detection of uric acid and folic acid in presence of interferences

Till to date, the application of sulfur-doped graphitic carbon nitride supported transition metal carbide interface for electrochemical sensor fabrication was less explored. In this work, we designed a simple synthesis of molybdenum carbide sphere embedded sulfur doped graphitic carbon nitride (Mo₂C/SCN) catalyst for the nanomolar electrochemical sensor application. The synthesized Mo₂C/SCN nanocatalyst was systematically characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) with elemental mapping. The SEM images show that the porous SCN network adhered uniformly on Mo₂C, causing a loss of crystallinity in the diffractogram. The corresponding elemental mapping of Mo₂C/SCN shows distinct peaks for carbon (41.47%), nitrogen (32.54%), sulfur (1.37%), and molybdenum (24.62%) with no additional impurity peaks, reflecting the successful synthesis. Later, the glassy carbon electrode (GCE) was modified by Mo₂C/SCN nanocatalyst for simultaneous sensing of uric acid (UA) and folic acid (FA). The fabricated Mo₂C/SCN/GCE is capable of simultaneous and interference free electrochemical detection of UA and FA in a binary mixture. The limit of detection (LOD) calculated at Mo₂C/SCN/GCE for UA and FA was 21.5 nM (0.09 - 47.0 μM) and 14.7 nM (0.09 - 167.25 μM) respectively by differential pulse voltammetric (DPV) technique. The presence of interferons has no significant effect on the sensor's performance, making it suitable for real sample analysis. The present method can be extended to fabricate an electrochemical sensor for various molecules.

Impact of Antioxidant Therapy on Natural Pregnancy Outcomes and Semen Parameters in Infertile Men: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

Seminal oxidative stress (OS) is a recognized factor potentially associated with male infertility, but the efficacy of antioxidant (AOX) therapy is controversial and there is no consensus on its utility. Primary outcomes of this study were to investigate the effect of AOX on spontaneous clinical pregnancy, live birth and miscarriage rates in male infertile patients. Secondary outcomes were conventional semen parameters, sperm DNA fragmentation (SDF) and seminal OS.

MATERIALS AND METHODS

Literature search was performed using Scopus, PubMed, Ovid, Embase, and Cochrane databases. Only randomized controlled trials (RCTs) were included and the meta-analysis was conducted according to PRISMA guidelines.

RESULTS

We assessed for eligibility 1,307 abstracts, and 45 RCTs were finally included, for a total of 4,332 infertile patients. We found a significantly higher pregnancy rate in patients treated with AOX compared to placebo-treated or untreated controls, without significant inter-study heterogeneity. No effects on live-birth or miscarriage rates were observed in four studies. A significantly higher sperm concentration, sperm progressive motility, sperm total motility, and normal sperm morphology was found in patients compared to controls. We found no effect on SDF in analysis of three eligible studies. Seminal levels of total antioxidant capacity were significantly higher, while seminal malondialdehyde acid was significantly lower in patients than controls. These results did not change after exclusion of studies performed following varicocele repair.

CONCLUSIONS

The present analysis upgrades the level of evidence favoring a recommendation for using AOX in male infertility to improve the spontaneous pregnancy rate and the conventional sperm parameters. The failure to demonstrate an increase in live-birth rate, despite an increase in pregnancy rates, is due to the very few RCTs specifically assessing the impact of AOX on live-birth rate. Therefore, further RCTs assessing the impact of AOX on live-birth rate and miscarriage rate, and SDF will be helpful.

Antioxidants for male subfertility

BACKGROUND

The inability to have children affects 10% to 15% of couples worldwide. A male factor is estimated to account for up to half of the infertility cases with between 25% to 87% of male subfertility considered to be due to the effect of oxidative stress. Oral supplementation with antioxidants is thought to improve sperm quality by reducing oxidative damage. Antioxidants are widely available and inexpensive when compared to other fertility treatments, however most antioxidants are uncontrolled by regulation and the evidence for their effectiveness is uncertain. We compared the benefits and risks of different antioxidants used for male subfertility.

OBJECTIVES

To evaluate the effectiveness and safety of supplementary oral antioxidants in subfertile men.

SEARCH METHODS

The Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, AMED, and two trial registers were searched on 15 February 2021, together with reference checking and contact with experts in the field to identify additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment, or treatment with another antioxidant, among subfertile men of a couple attending a reproductive clinic. We excluded studies comparing antioxidants with fertility drugs alone and studies that included men with idiopathic infertility and normal semen parameters or fertile men attending a fertility clinic because of female partner infertility.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. The primary review outcome was live birth. Clinical pregnancy, adverse events and sperm parameters were secondary outcomes.

MAIN RESULTS

We included 90 studies with a total population of 10,303 subfertile men, aged between 18 and 65 years, part of a couple who had been referred to a fertility clinic and some of whom were undergoing medically assisted reproduction (MAR). Investigators compared and combined 20 different oral antioxidants. The evidence was of 'low' to 'very low' certainty: the main limitation was that out of the 67 included studies in the meta-analysis only 20 studies reported clinical pregnancy, and of those 12 reported on live birth. The evidence is current up to February 2021. Live birth: antioxidants may lead to increased live birth rates (odds ratio (OR) 1.43, 95% confidence interval (CI) 1.07 to 1.91, P = 0.02, 12 RCTs, 1283 men, I2 = 44%, very low-certainty evidence). Results in the studies contributing to the analysis of live birth rate suggest that if the baseline chance of live birth following placebo or no treatment is assumed to be 16%, the chance following the use of antioxidants is estimated to be between 17% and 27%. However, this result was based on only 246 live births from 1283 couples in 12 small or medium-sized studies. When studies at high risk of bias were removed from the analysis, there was no evidence of increased live birth (Peto OR 1.22, 95% CI 0.85 to 1.75, 827 men, 8 RCTs, P = 0.27, I2 = 32%). Clinical pregnancy rate: antioxidants may lead to increased clinical pregnancy rates (OR 1.89, 95% CI 1.45 to 2.47, P < 0.00001, 20 RCTs, 1706 men, I2 = 3%, low-certainty evidence) compared with placebo or no treatment. This suggests that, in the studies contributing to the analysis of clinical pregnancy, if the baseline chance of clinical pregnancy following placebo or no treatment is assumed to be 15%, the chance following the use of antioxidants is estimated to be between 20% and 30%. This result was based on 327 clinical pregnancies from 1706 couples in 20 small studies. Adverse events Miscarriage: only six studies reported on this outcome and the event rate was very low. No evidence of a difference in miscarriage rate was found between the antioxidant and placebo or no treatment group (OR 1.46, 95% CI 0.75 to 2.83, P = 0.27, 6 RCTs, 664 men, I2 = 35%, very low-certainty evidence). The findings suggest that in a population of subfertile couples, with male factor infertility, with an expected miscarriage rate of 5%, the risk of miscarriage following the use of an antioxidant would be between 4% and 13%. Gastrointestinal: antioxidants may lead to an increase in mild gastrointestinal discomfort when compared with placebo or no treatment (OR 2.70, 95% CI 1.46 to 4.99, P = 0.002, 16 RCTs, 1355 men, I2 = 40%, low-certainty evidence). This suggests that if the chance of gastrointestinal discomfort following placebo or no treatment is assumed to be 2%, the chance following the use of antioxidants is estimated to be between 2% and 7%. However, this result was based on a low event rate of 46 out of 1355 men in 16 small or medium-sized studies, and the certainty of the evidence was rated low and heterogeneity was high. We were unable to draw conclusions from the antioxidant versus antioxidant comparison as insufficient studies compared the same interventions.

AUTHORS' CONCLUSIONS

In this review, there is very low-certainty evidence from 12 small or medium-sized randomised controlled trials suggesting that antioxidant supplementation in subfertile males may improve live birth rates for couples attending fertility clinics. Low-certainty evidence suggests that clinical pregnancy rates may increase. There is no evidence of increased risk of miscarriage, however antioxidants may give more mild gastrointestinal discomfort, based on very low-certainty evidence. Subfertile couples should be advised that overall, the current evidence is inconclusive based on serious risk of bias due to poor reporting of methods of randomisation, failure to report on the clinical outcomes live birth rate and clinical pregnancy, often unclear or even high attrition, and also imprecision due to often low event rates and small overall sample sizes. Further large well-designed randomised placebo-controlled trials studying infertile men and reporting on pregnancy and live births are still required to clarify the exact role of antioxidants.

Outcome reporting across randomized controlled trials evaluating potential treatments for male infertility: a systematic review

STUDY QUESTION

What are the primary outcomes and outcome measures used in randomized controlled trials (RCTs) evaluating potential treatments for male infertility in the last 10 years?

SUMMARY ANSWER

Outcome reporting across male infertility trials is heterogeneous with numerous definitions and measures used to define similar outcomes.

WHAT IS KNOWN ALREADY

No core outcome set for male infertility trials has been developed. Male infertility trials are unique in that they have potentially three participants, a man, a female partner and their offspring and this will likely lead to significant variation in outcome reporting in randomized trials.

STUDY DESIGN SIZE DURATION

A systematic review of RCTs mapping outcomes and outcome measures evaluating potential treatments for men with infertility registered in the Cochrane Register of Controlled Trials (CENTRAL) between January 2010 and July 2021.

PARTICIPANTS/MATERIALS SETTING METHODS

Abstract screening and study selection was undertaken in duplicate using a review protocol that was developed prior to commencing the review. No risk of bias assessment was undertaken as this review aims to report on outcome reporting only.

MAIN RESULTS AND THE ROLE OF CHANCE

One hundred and seventy-five RCTs were identified, and given the large number of studies we limited our review to the 100 largest trials. Seventy-nine different treatments were reported across the 100 largest RCTs including vitamin and dietary supplements (18 trials), surgical treatments (18 trials) and sperm selection techniques (22 trials). When considering the largest 100 trials (range: 80-2772 participants), 36 primary and 89 secondary outcomes were reported. Forty-seven trials reported a primary outcome and 36 trials clearly defined their primary outcome. Pregnancy outcomes were inconsistently reported and included pregnancy rate (51 trials), pregnancy loss including miscarriage, ectopic pregnancy, stillbirth (9 trials) and live birth (13 trials). Trials consistently reporting the same outcome frequently used different definitions. For example, semen quality was reported by 75 trials and was defined in 7 different ways, including; the World Health Organization (WHO) 2010 criteria (32 trials), WHO 1999 criteria (18 trials), WHO 1992 criteria (3 trials), WHO 1999 and 1992 criteria (1 trial) and the Kruger strict morphology criteria (1 trial).

LIMITATIONS REASONS FOR CAUTION

We only evaluated the 100 largest trials published in the last 10 years and did not report outcomes on the remaining 75. An outcome was included as a primary outcome only if clearly stated in the manuscript and we did not contact authors to clarify this. As our review mapped outcomes and outcome measures, we did not undertake an integrity assessment of the trials included in our review.

WIDER IMPLICATIONS OF THE FINDINGS

Most randomized trials evaluating treatments for male infertility report different outcomes. Only half of the RCTs reported pregnancy rate and even fewer reported live birth; furthermore, the definitions of these outcomes varies across trials. Developing, disseminating and implementing a minimum data set, known as a core outcome set, for male infertility research could help to improve outcome selection, collection and reporting.

STUDY FUNDING/COMPETING INTERESTS

A.P.-chairman of external scientific advisory committee of Cryos International Denmark ApS, member of the scientific advisory board for Cytoswim LDT and ExSeed Health. Guest lecture at the 'Insights for Fertility Conference', funded by MERK SERONO Limited. M.v.W.-holds a ZON-MW research grant. No external funding was obtained for this study.

Systematic Review and Critical Analysis on Dietary Supplements for Male Infertility: From a Blend of Ingredients to a Rationale Strategy

Content

Dietary supplements (DS) for male infertility marketed in Italy were evaluated for composition, concentration of ingredients, and recommended daily dose. A systematic review of literature identified ingredients potentially effective on sperm parameters and their minimal effective daily dose (mED).

Objective

This study was conducted in order to critically evaluate the composition and efficacy of DS marketed in Italy.

Design Setting and Participants

This was a systematic review of randomized controlled trials.

Evidence Acquisition

A formula allowed us to classify the expected efficacy of each DS, based on composition. Each DS was scored and included into three classes of expected efficacy: high, low, and none.

Evidence Synthesis

Among 24 supplements, 3 (12.5%) fall in high, 9 (37.5%) in lower, and 12 (50.0%) in no expected efficacy class. DS composition showed 36 substances, 18 with no literature on male fertility and 18 showing positive effect on sperm parameters, thus considered potentially active ingredients (PAI). All DS were mixtures of ingredients, containing from 2 to 17 different substances. Fifteen supplements (65.2%) contained at least 1 ingredient without evidence of efficacy and 21 formulations had PAI dosed below mED. Some PAI were associated to the improvement of specific sperm parameters.

Conclusions

DS were usually blends of many substances that are frequently employed at negligible dose or without any evidence of efficacy on male reproduction. Some ingredients have been demonstrated to be effective on specific sperm parameters by RCTs. We report a list of ingredients with potential efficacy on specific sperm parameters, aimed to allow a tailored use of DS.

Patient Summary

The market of DS for male infertility offers products with potential efficacy in the improvement of sperm parameters but also many with uncertain effects. Based on current scientific literature, our study can help in the choice of DS that are more likely to be effective on specific sperm alterations, so providing the best supplementation for each patient.

Comparative Potential of Zinc Sulfate, L-Carnitine, Lycopene, and Coenzyme Q10 on Cadmium-Induced Male Infertility

The human exposure to toxic chemicals and heavy metals is one of the main predisposing factors contributing to male infertility. Acute exposure to cadmium chloride results in testicular damage and infertility. The purpose of the present study was to investigate and compare the curative effect of coenzyme Q10 (CoQ10), lycopene, L-carnitine (LC), and zinc sulfate against the cadmium-induced infertility in male Wistar rats. Cadmium chloride (0.4 mg/kg/day) was orally administered to rats for three consecutive days. Then, oral administration of different treatments (i.e., LC 100 mg/kg, CoQ10 20 mg/kg, lycopene 4 mg/kg, zinc sulfate 6 mg/kg, and a combination LC-CoQ10 at 500/50 mg/kg) was carried out for 30 days. The impact of different treatments on semen parameters, such as sperm count and motility, testicular antioxidants, and serum testosterone, was determined. Furthermore, the morphology of epididymis sperms and histopathology of rat testes were also assessed. Cadmium exposure decreased the sperm count, progressive sperm motility, testosterone, superoxide dismutase (SOD), and catalase and reduced glutathione (GSH). It also caused banana sperm tail, bent sperm head, vacuolization of seminiferous tubules, and oligospermia in rat testes. All treatments with nutraceuticals improved sperm count, sperm morphology, serum testosterone, vacuolization of seminiferous tubules, and oligospermia in diseased rats. Treatment with lycopene, LC, and LC-CoQ10 improved progressive sperm motility and other parameters and increased SOD, GSH, and CAT in the rat testes. CoQ10 also increased SOD activity in rat testes' tissue homogenates. It is concluded from the current study that all nutraceuticals partially improved reproductive toxicity of cadmium. The administration of lycopene and a high-dose combination of LC-CoQ10 were more efficacious in treating cadmium-induced infertility than other treatments. Treatment of cadmium-exposed rats with lycopene, LC, CoQ10, and LC-CoQ10 improved sperm count and motility through reduction of testicular oxidative stress and improving serum testosterone.

Electrochemical investigations and theoretical studies of biocompatible niacin-modified carbon paste electrode interface for electrochemical sensing of folic acid

The modified electrode–analyte interaction is critical in establishing the sensing mechanism and in developing an electrochemical sensor. Here, the niacin-modified carbon paste electrode (NC/CPE) was fabricated for electrochemical sensing applications. The two stable structures of the niacin were optimized and confirmed by the absence of negative vibrational frequency, at B3LYP and B3LYP-GD3BJ level and 6–311 g** basis set. The physical and quantum chemical quantities were used to explain the molecular stability and electronic structure-related properties of the niacin. The natural bond orbital (NBO) analysis was performed to disclose the donor–acceptor interactions that were a critical role in explaining the modifier–analyte interaction. The fabricated NC/CPE was used for the determination of folic acid (FA) in physiological pH by cyclic voltammetry (CV) method. The limit of detection (LOD) for FA at NC/CPE was calculated to be 0.09 µM in the linear concentration range of 5.0 µM to 45.0 µM (0.2 M PBS, pH 7.4) by CV technique. The analytical applicability of the NC/CPE was evaluated in real samples, such as fruit juice and pharmaceutical sample, and the obtained results were acceptable. The HOMO and LUMO densities are used to identify the nucleophilic and electrophilic regions of niacin. The use of density functional theory-based quantum chemical simulations to understand the sensory performance of the modifier has laid a new foundation for fabricating electrochemical sensing platforms.

The Effect of Antioxidant Supplementation on Operated or Non-Operated Varicocele-Associated Infertility: A Systematic Review and Meta-Analysis

In patients with varicocele-associated infertility, the effect of antioxidant supplementation on fertility is unknown. We performed a systematic review and meta-analysis to explore their role in patients with operated or non-operated varicocele. We searched major databases and sources of grey literature until May 2021 (PROSPERO: CRD42021248195). We included 14 studies (980 individuals) in the systematic review. Of the 14 studies, 2 explored the effect of antioxidant supplementation in patients with non-operated varicocele, 1 compared antioxidants versus surgical repair of varicocele, while 11 explored antioxidants after surgical repair of varicocele and were also included in the meta-analysis. Regarding pregnancy rates, no significant differences were demonstrated after treatment with antioxidants versus no treatment at three (OR: 2.28, 95% CI: 0.7-7.48) and six months (OR: 1.88, 95% CI: 0.62-5.72). Accordingly, contradictory findings were reported in sperm concentration, morphology, and motility, as well as DNA fragmentation. Our findings indicate that antioxidant supplementation does not improve pregnancy rates and semen parameters in patients with varicocele-associated infertility, in the absence of previous screening for oxidative stress. Based on the previous notion, most included studies also raised methodological concerns. Therefore, definitive conclusions about the efficacy of antioxidant supplementation in this setting cannot be drawn and further research on the field is mandatory.

Dietary Antioxidants in the Treatment of Male Infertility: Counteracting Oxidative Stress

Infertility affects about 15% of the population and male factors only are responsible for ~25-30% of cases of infertility. Currently, the etiology of suboptimal semen quality is poorly understood, and many environmental and genetic factors, including oxidative stress, have been implicated. Oxidative stress is an imbalance between the production of free radicals, or reactive oxygen species (ROS), and the capacity of the body to counteract their harmful effects through neutralization by antioxidants. The purpose of this review, by employing the joint expertise of international researchers specialized in nutrition and male fertility areas, is to update the knowledge about the reproductive consequences of excessive ROS concentrations and oxidative stress on the semen quality and Assisted Reproduction Techniques (ART) clinical outcomes, to discuss the role of antioxidants in fertility outcomes, and finally to discuss why foods and dietary patterns are more innocuous long term solution for ameliorating oxidative stress and therefore semen quality results and ART fertility outcomes. Since this is a narrative review and not a systematic/meta-analysis, the summarized information in the present study should be considered cautiously.

Nutrition, genetic variation and male fertility

Infertility affects nearly 50 million couples worldwide, with 40-50% of cases having a male factor component. It is well established that nutritional status impacts reproductive development, health and function, although the exact mechanisms have not been fully elucidated. Genetic variation that affects nutrient metabolism may impact fertility through nutrigenetic mechanisms. This review summarizes current knowledge on the role of several dietary components (vitamins A, B₁₂, C, D, E, folate, betaine, choline, calcium, iron, caffeine, fiber, sugar, dietary fat, and gluten) in male reproductive health. Evidence of gene-nutrient interactions and their potential effect on fertility is also examined. Understanding the relationship between genetic variation, nutrition and male fertility is key to developing personalized, DNA-based dietary recommendations to enhance the fertility of men who have difficulty conceiving.

Potential Role of Zinc in the COVID-19 Disease Process and its Probable Impact on Reproduction

COVID-19 (coronavirus disease 2019) is the current world health crisis, producing extensive morbidity and mortality across all age groups. Given the established roles of zinc in combating oxidative damage and viral infections, zinc is being trialed as a treatment modality against COVID-19. Zinc also has confirmed roles in both male and female reproduction. The possible depletion of zinc with the oxidative events of COVID-19 is especially relevant to the fertility of affected couples. This review aims to present the pathophysiology of COVID-19, especially in relation to reproductive function; the role of zinc in the COVID-19 disease process; and how zinc depletion in concert with cytokine storm and reactive oxygen species production could affect reproduction. It also highlights research areas to better the understanding of COVID-19 and its impact on fertility and potential ways to mitigate the impact.

Dietary supplements in the management of varicocele-induced infertility: A review of potential mechanisms

Varicocele is a main cause of lower production of spermatozoon and infertility with multiple pathophysiological mechanisms. In the past decades, the use of dietary supplements has significantly increased due to both the modern lifestyle and the food shortages of the industrialised countries. The purpose of this review paper is to collect scientific evidences from basic and clinical studies which support the use of dietary supplements to define the clinical framework for patients with varicocele. In the present review, we used keywords such as dietary supplements, varicocele, male infertility, oxidative stress, DNA fragmentation, sperm parameters to find the proper articles. The standard search biomedical engines were used for seeking the papers. The use of dietary supplements such as minerals, vitamins and antioxidants has an essential role in the prevention and treatment of varicocele by increasing the levels of antioxidant enzymes (e.g. peroxidase, superoxide dismutase and catalase) and decreasing the levels of inflammatory markers (e.g. tumour necrosis factor-α, interleukin-6 and interleukin-1) in testis. According to the results, the dietary supplements may alleviate the spermatogenesis in varicocele patients through different mechanisms such as suppression of stress oxidative and inflammation in testicular tissue.

Fumaria parviflora regulates oxidative stress and apoptosis gene expression in the rat model of varicocele induction

Varicocele is one of the leading causes of male infertility in which oxidative stress induces DNA damages in spermatozoa of patients with varicocele. Recent studies indicated that the treatment with antioxidant agents has protective effects against the formation of reactive oxygen species (ROS). Our research aimed to evaluate the impact of Fumaria Parviflora (FP) on the varicocele-induced testicular injury. For this purpose, 32 adult male Wistar rats (n = 8 per group) were randomly assigned to four groups as follows: sham group, varicocele group, varicocele treatment group and the control treatment group. The experimental groups daily received FP (250 mg/kg) for 8 weeks. The induction of varicocele was conducted by partial occlusion on the left renal vein. The diameter of seminiferous tubules, Johnsen's score and the epithelium thickness improved in the treated-varicocele group as compared to the varicocele group. FP extract could increase the biochemical parameters including superoxide dismutase and glutathione peroxidase, and also decrease malondialdehyde level in the varicocele group. Furthermore, varicocele markedly increased both mRNA and intensity of Bax, while treatment with FP could alleviate them. We concluded that FP could alleviate varicocele, possibly by lowering oxidative stress and testicular damage.

Dietary Supplements for Male Infertility: A Critical Evaluation of Their Composition

Dietary supplements (DS) represent a possible approach to improve sperm parameters and male fertility. A wide range of DS containing different nutrients is now available. Although many authors demonstrated benefits from some nutrients in the improvement of sperm parameters, their real effectiveness is still under debate. The aim of this study was to critically review the composition of DS using the Italian market as a sample. Active ingredients and their minimal effective daily dose (mED) on sperm parameters were identified through a literature search. Thereafter, we created a formula to classify the expected efficacy of each DS. Considering active ingredients, their concentration and the recommended daily dose, DS were scored into three classes of expected efficacy: higher, lower and none. Twenty-one DS were identified. Most of them had a large number of ingredients, frequently at doses below mED or with undemonstrated efficacy. Zinc was the most common ingredient of DS (70% of products), followed by selenium, arginine, coenzyme Q and folic acid. By applying our scoring system, 9.5% of DS fell in a higher class, 71.4% in a lower class and 19.1% in the class with no expected efficacy. DS marketed in Italy for male infertility frequently includes effective ingredients but also a large number of substances at insufficient doses or with no reported efficacy. Manufacturers and physicians should better consider the scientific evidence on effective ingredients and their doses before formulating and prescribing these products.

Dietary supplementation with a novel l-carnitine multi-micronutrient in idiopathic male subfertility involving oligo-, astheno-, teratozoospermia: A randomized clinical study

OBJECTIVE

To study the influence of a multi-component nutrient dietary supplement on sperm parameters and pregnancy rates in idiopathic male infertility (IMI) with oligo-, astheno-, and teratozoospermia.

DESIGN

A randomized, double-blind, placebo-controlled, prospective, parallel arms (1:1 allocation ratio), multi-center clinical trial.

SETTINGS

Eight urology/reproductive health clinical centers located in Ukraine.

PATIENTS

Eighty-three males aged 21-50 years with IMI and at least 1 of 3 abnormal values: total sperm concentration < 15 million/ml or/and spermatozoa progressive motility < 32% or/and forms with normal morphology < 4%.

INTERVENTION(S)

Patients were randomly allocated verum test dietary supplement (TDS) containing l-carnitine/acetyl-l-carnitine, l-arginine, glutathione, co-enzyme Q10, zinc, vitamin B₉ , vitamin B₁₂ , selenium, or placebo 1 time daily for 6 months.

MAIN OUTCOME(S)

The primary outcome measure was the percentage of normal spermiograms (concentration ≥ 15 million/ml and ≥ 32% of spermatozoa with progressive motility and ≥ 4% of normal forms) at month 0, 2, and 4. The percentage of pregnancies served the secondary outcome endpoint. Differences between the groups were assessed in z-test for proportions.

RESULTS

All males finished the study. At month 4, 29/42 (69.0%) males in the verum and 9/41 (22.0%) had normal spermiograms (P < .001). The percentage of spontaneous pregnancies in the verum group was greater than in the placebo group (10/42, 23.8% vs. 2/41, 4.9%, respectively, P = .017). There were no reportable supplement-associated adverse events.

CONCLUSION

Specific multi-nutrient combination l-carnitine/l-acetyl-carnitine, l-arginine, glutathione, co-enzyme-Q, zinc, folic acid, cyanocobalamin, and selenium can improve sperm quality in males with IMI and increase pregnancy rates.

Pathophysiology and treatment options of varicocele: An overview

Varicocele is the most common correctable cause for male infertility, but not all men with varicocele are affected equally by this condition. The pathophysiology of varicocele-induced fertility remains ill-defined. While evidence suggests that oxidative stress remains a central factor, other mechanisms likely include scrotal hyperthermia, reflux of metabolites, hypoxia and cadmium accumulation. Microsurgical varicocelectomy remains the gold standard treatment option for infertile men with a clinically palpable varicocele and abnormal semen parameters. Newer evidence suggests a potential role for antioxidant supplementation and a meaningful role of varicocelectomy for patients destined for ART to improve pregnancy outcomes.

A Randomized Trial to Evaluate the Effects of Folic Acid and Zinc Supplementation on Male Fertility and Livebirth: Design and Baseline Characteristics

The Folic Acid and Zinc Supplementation Trial (FAZST) was a multicenter, double-blind, block-randomized, placebo-controlled trial to determine whether folic acid and zinc supplementation in men improves semen quality and increases livebirth rate among couples seeking infertility treatment (2013-2017). Eligible men were aged 18 years or older with female partners aged 18-45 years, seeking infertility treatment. Men were randomized (1:1) to 5 mg folic acid and 30 mg elemental zinc daily or matching placebo for 6 months. Randomization was stratified by site and intended infertility treatment (in vitro fertilization (IVF), non-IVF/study site, and non-IVF/outside clinic). Follow-up of men continued for 6 months, and female partners were passively followed for a minimum of 9 months. Women who conceived were followed throughout pregnancy. Overall, 2,370 men were randomized during 2013-2017 (1,185 folic acid and zinc, 1,185 placebo); they had a mean age of 33 years and body mass index (weight (kg)/height (m)2) of 29.8. Most participants were white (82%), well educated (83% with some college), and employed (72%). Participant characteristics were balanced across intervention arms. Study visits were completed by 89%, 77%, and 75% of men at months 2, 4, and 6, respectively. Here we describe the study design, recruitment, data collection, lessons learned, and baseline participant characteristics.

Effect of Folic Acid and Zinc Supplementation in Men on Semen Quality and Live Birth Among Couples Undergoing Infertility Treatment: A Randomized Clinical Trial

IMPORTANCE

Dietary supplements marketed for male fertility commonly contain folic acid and zinc based on limited prior evidence for improving semen quality. However, no large-scale trial has examined the efficacy of this therapy for improving semen quality or live birth.

OBJECTIVE

To determine the effect of daily folic acid and zinc supplementation on semen quality and live birth.

DESIGN, SETTING, AND PARTICIPANTS

The Folic Acid and Zinc Supplementation Trial was a multicenter randomized clinical trial. Couples (n = 2370; men aged ≥18 years and women aged 18-45 years) planning infertility treatment were enrolled at 4 US reproductive endocrinology and infertility care study centers between June 2013 and December 2017. The last 6-month study visit for semen collection occurred during August 2018, with chart abstraction of live birth and pregnancy information completed during April 2019.

INTERVENTIONS

Men were block randomized by study center and planned infertility treatment (in vitro fertilization, other treatment at a study site, and other treatment at an outside clinic) to receive either 5 mg of folic acid and 30 mg of elemental zinc (n = 1185) or placebo (n = 1185) daily for 6 months.

MAIN OUTCOMES AND MEASURES

The co-primary outcomes were live birth (resulting from pregnancies occurring within 9 months of randomization) and semen quality parameters (sperm concentration, motility, morphology, volume, DNA fragmentation, and total motile sperm count) at 6 months after randomization.

RESULTS

Among 2370 men who were randomized (mean age, 33 years), 1773 (75%) attended the final 6-month study visit. Live birth outcomes were available for all couples, and 1629 men (69%) had semen available for analysis at 6 months after randomization. Live birth was not significantly different between treatment groups (404 [34%] in the folic acid and zinc group and 416 [35%] in the placebo group; risk difference, -0.9% [95% CI, -4.7% to 2.8%]). Most of the semen quality parameters (sperm concentration, motility, morphology, volume, and total motile sperm count) were not significantly different between treatment groups at 6 months after randomization. A statistically significant increase in DNA fragmentation was observed with folic acid and zinc supplementation (mean of 29.7% for percentage of DNA fragmentation in the folic acid and zinc group and 27.2% in the placebo group; mean difference, 2.4% [95% CI, 0.5% to 4.4%]). Gastrointestinal symptoms were more common with folic acid and zinc supplementation compared with placebo (abdominal discomfort or pain: 66 [6%] vs 40 [3%], respectively; nausea: 50 [4%] vs 24 [2%]; and vomiting: 32 [3%] vs 17 [1%]).

CONCLUSIONS AND RELEVANCE

Among a general population of couples seeking infertility treatment, the use of folic acid and zinc supplementation by male partners, compared with placebo, did not significantly improve semen quality or couples' live birth rates. These findings do not support the use of folic acid and zinc supplementation by male partners in the treatment of infertility.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01857310.

Efficacy of antioxidant therapy on sperm quality measurements after varicocelectomy: A systematic review and meta-analysis

Antioxidants were proved to be efficient to improve the quality of spermatozoa after varicocelectomy. We carried out a systematic review and performed a meta-analysis to evaluate the efficacy of antioxidant therapy in sperm parameters' quality after varicocelectomy during 3 or 6 months' treatment cycle. During research, randomised controlled trials were searched by MEDLINE, EMBASE and the Cochrane Controlled Trials Register, and necessary parameters were compared between two groups after varicocelectomy. Finally, six studies including 576 patients were included in our meta-analysis. As for sperm parameters, significant improvements of sperm concentration (p < .0001), sperm motility (p = .03), progressive sperm motility (p < .00001) and sperm morphology (p < .00001) were existed in antioxidant group 3 months after varicocelectomy. With regard to the 6 months' outcomes, sperm parameters were improved as well except sperm motility (p = .72) and progressive sperm motility (p = .57). Referring to pregnancy rate, no significant difference was existed between two groups (p = .36), and the FSH level of antioxidant group was lower than placebo group 3 or 6 months after varicocelectomy (3 months, p = .02; 6 months, p = .03). In conclusion, compared with the placebo, the antioxidant therapy after varicocelectomy can improve the quality of sperm parameters and construct a favourable living condition for spermatozoa by reducing FSH level.

Antioxidants for male subfertility

BACKGROUND

The inability to have children affects 10% to 15% of couples worldwide. A male factor is estimated to account for up to half of the infertility cases with between 25% to 87% of male subfertility considered to be due to the effect of oxidative stress. Oral supplementation with antioxidants is thought to improve sperm quality by reducing oxidative damage. Antioxidants are widely available and inexpensive when compared to other fertility treatments, however most antioxidants are uncontrolled by regulation and the evidence for their effectiveness is uncertain. We compared the benefits and risks of different antioxidants used for male subfertility. This review did not examine the use of antioxidants in normospermic men.

OBJECTIVES

To evaluate the effectiveness and safety of supplementary oral antioxidants in subfertile men.

SEARCH METHODS

The Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and two trials registers were searched on 1 February 2018, together with reference checking and contact with study authors and experts in the field to identify additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment or treatment with another antioxidant, among subfertile men of a couple attending a reproductive clinic. We excluded studies comparing antioxidants with fertility drugs alone and studies that included fertile men attending a fertility clinic because of female partner infertility.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. The primary review outcome was live birth. Clinical pregnancy, adverse events and sperm parameters were secondary outcomes.

MAIN RESULTS

We included 61 studies with a total population of 6264 subfertile men, aged between 18 and 65 years, part of a couple who had been referred to a fertility clinic and some of whom were undergoing assisted reproductive techniques (ART). Investigators compared and combined 18 different oral antioxidants. The evidence was of 'low' to 'very low' quality: the main limitation was that out of the 44 included studies in the meta-analysis only 12 studies reported on live birth or clinical pregnancy. The evidence is current up to February 2018.Live birth: antioxidants may lead to increased live birth rates (OR 1.79, 95% CI 1.20 to 2.67, P = 0.005, 7 RCTs, 750 men, I2 = 40%, low-quality evidence). Results suggest that if in the studies contributing to the analysis of live birth rate, the baseline chance of live birth following placebo or no treatment is assumed to be 12%, the chance following the use of antioxidants is estimated to be between 14% and 26%. However, this result was based on only 124 live births from 750 couples in seven relatively small studies. When studies at high risk of bias were removed from the analysis, there was no evidence of increased live birth (Peto OR 1.38, 95% CI 0.89 to 2.16; participants = 540 men, 5 RCTs, P = 0.15, I2 = 0%).Clinical pregnancy rate: antioxidants may lead to increased clinical pregnancy rates (OR 2.97, 95% CI 1.91 to 4.63, P < 0.0001, 11 RCTs, 786 men, I2 = 0%, low-quality evidence) compared to placebo or no treatment. This suggests that if in the studies contributing to the analysis of clinical pregnancy, the baseline chance of clinical pregnancy following placebo or no treatment is assumed to be 7%, the chance following the use of antioxidants is estimated to be between 12% and 26%. This result was based on 105 clinical pregnancies from 786 couples in 11 small studies.Adverse eventsMiscarriage: only three studies reported on this outcome and the event rate was very low. There was no difference in miscarriage rate between the antioxidant and placebo or no treatment group (OR 1.74, 95% CI 0.40 to 7.60, P = 0.46, 3 RCTs, 247 men, I2 = 0%, very low-quality evidence). The findings suggest that in a population of subfertile men with an expected miscarriage rate of 2%, the chance following the use of an antioxidant would result in the risk of a miscarriage between 1% and 13%.Gastrointestinal: antioxidants may lead to an increase in mild gastrointestinal upsets when compared to placebo or no treatment (OR 2.51, 95% CI 1.25 to 5.03, P = 0.010, 11 RCTs, 948 men, I2 = 50%, very low-quality evidence). This suggests that if the chance of gastrointestinal upsets following placebo or no treatment is assumed to be 2%, the chance following the use of antioxidants is estimated to be between 2% and 9%. However, this result was based on a low event rate of 35 out of 948 men in 10 small or medium-sized studies, and the quality of the evidence was rated very low and was high in heterogeneity.We were unable to draw any conclusions from the antioxidant versus antioxidant comparison as insufficient studies compared the same interventions.

AUTHORS' CONCLUSIONS

In this review, there is low-quality evidence from seven small randomised controlled trials suggesting that antioxidant supplementation in subfertile males may improve live birth rates for couples attending fertility clinics. Low-quality evidence suggests that clinical pregnancy rates may also increase. Overall, there is no evidence of increased risk of miscarriage, however antioxidants may give more mild gastrointestinal upsets but the evidence is of very low quality. Subfertilte couples should be advised that overall, the current evidence is inconclusive based on serious risk of bias due to poor reporting of methods of randomisation, failure to report on the clinical outcomes live birth rate and clinical pregnancy, often unclear or even high attrition, and also imprecision due to often low event rates and small overall sample sizes. Further large well-designed randomised placebo-controlled trials reporting on pregnancy and live births are still required to clarify the exact role of antioxidants.

Effect of adjuvant drug therapy after varicocelectomy on fertility outcome in males with varicocele-associated infertility: Systematic review and meta-analysis

Varicocele is one of the common correctable causes of male infertility. Recent studies have demonstrated varicocelectomy in males with abnormal semen parameters was associated with better fertility outcome, but the effect of adjuvant drug therapy after varicocelectomy on fertility outcome in patients with varicocele-associated infertility remains undefined. Hence, the present meta-analysis was performed to assess the efficacy of adjuvant drug therapy after varicocelectomy. The protocol was registered with PROSPERO (No. CRD42018093749). Ten randomised controlled trails containing 533 patients with adjuvant drug therapy after varicocelectomy and 368 patients with no medical treatment after varicocelectomy were included. Our analysis revealed that the improvement in pregnancy rate after adjuvant drug therapy was insignificant. (OR = 1.70, 95%CI = 0.99-2.91), but resulted in significant improvements in sperm concentration (MD = 13.71, 95%CI = 5.80-21.63) and motility (MD = 4.77, 95%CI = 3.98-5.56) at 3 months, sperm DNA integrity (SMD = 3.13, 95%CI = 1.50-4.75) and serum FSH level (MD = -1.02, 95%CI = -1.79 to -0.24). Therefore, compared to no medical treatment, the adjuvant drug therapy, especially the use of antioxidants seems to be associated with better fertility outcome. However, more evidences with high-quality studies are necessary to conform its benefits.

Effect of folate deficiency on promoter methylation and gene expression of Esr1, Cav1, and Elavl1, and its influence on spermatogenesis

This study aims to investigate the effect of folate deficiency on the male reproductive function and the underlying mechanism. A total of 269 screened participants from 421 recruitments were enrolled in this study. An animal model of folate deficiency was constructed. Folate concentration was measured in the ejaculate, and its association with semen parameters was then determined. The expression and promoter methylation status of ESR1, CAV1, and ELAVL1 were also evaluated. Results showed that seminal plasma folate level was significantly lower among subjects with azoospermia than those with normozoospermia. Low folate level was significantly correlated with low sperm concentration in men with normozoospermia. Folate deficiency significantly reduced the expression of ESR1, CAV1, and ELAVL1, which are critical to spermatogenesis. However, low folate levels did not increase the methylation levels of the promoter regions of ESR1, CAV1, and ELAVL1 in human sperm DNA. Thus, folate deficiency impairs spermatogenesis may partly due to inhibiting the expression of these genes. Thus future research should determine the significance of sufficient folate status in male fertilization and subsequent pregnancy outcomes.

Effects of administration of co-trimoxazole and folic acid on sperm quality and histological changes of testes in male rats

BACKGROUND

Male infertility has been reported following long-term sulfasalazine, however, the precise effects of co-trimoxazole on sperm quality is controversial.

OBJECTIVE

In this study, we evaluated the effects of co-trimoxazole and its co-administration with folic acid on sperm quality and histological changes of testes in male rats.

MATERIALS AND METHODS

In this experimental study, 136 male Wistar rats were divided into 9 groups: I (control), II (vehicle) received saline, III: received folic acid (1 mg/kg /daily i.p., and IV- IX received co-trimoxazole (30, 60, and 120 mg/kg/daily; i.p.)+folic acid (1 mg/kg/daily; i.p.) for 14 or 28 days. Sperm samples were obtained from each group at the end of 14^th and 28^th days. Sperm numbers, motility, and viability were evaluated on a hemocytometer. Hematoxylin and Eosin stained testes were done for evaluation ofthe number of Leydig cells, vascularity, spermatids, spermatocytes, and means of seminiferous tubules diameter under light microscopy.

RESULTS

Co-trimoxazole treatment for either 14 or 28 days caused a significant decrease in the percentage of sperm number, motility, and viability (p<0.001) compared to the control group. Also, high doses of co-trimoxazole caused a significant decrease in testes structural abnormalities means of seminiferous tubules diameter, spermatids, and spermatogonia) compared to the vehicle group (p<0.001). Folic acid co-administration with co-trimoxazole partially reversed the decrease in sperm quality and structural abnormalities of high doses of co-trimoxazole (60 and 120 mg/kg/daily) (p<0.001).

CONCLUSION

The data showed the adverse effects of co-trimoxazole on sperm quality and testes morphology which was protected partially by folic acid co-administration in rats. The underlying mechanism (s) needs further investigations.

An update on the role of medical treatment including antioxidant therapy in varicocele

Varicocele-associated male infertility has classically been managed using surgery or assisted reproductive techniques. With increasing evidence of oxidative stress as a pathophysiological factor in varicocele-associated infertility, medical therapy especially antioxidants might become a treatment option with lower risks. We reviewed the existing literature on the role of various medical agents in the management of male infertility attributed to varicoceles. Medical therapy is typically evaluated in three different situations such as (a) comparison of two drugs or one drug with placebo, (b) comparison of drugs versus surgery, and (c) comparison of drugs as adjuvant therapy with surgery versus drug therapy alone. Due to heterogeneity of data and lack of well-conducted studies, there is insufficient data to recommend routine use of medical therapy for men with varicocele-associated infertility and surgery remains the treatment of choice. Pregnancy and live birth rates are usually not reported in most studies and mere improvement in sperm parameters or antioxidant capacity is insufficient to support its routine use. Antioxidant therapy is a potential option due to its theoretical benefit, data from preclinical studies, and lack of major side effects. Adjuvant therapy with antioxidants after surgical repair of varicocele may improve the outcome and is a potential area for further research.

Current medical management of endocrine-related male infertility

Male factor contributes to 50%-60% of overall infertility but is solely responsible in only 20% of couples. Although most male factor infertility is ascertained from an abnormal semen analysis, other male factors can be contributory especially if the sample returns normal. Male infertility can be due to identifiable hormonal or anatomical etiologies that may be reversible or irreversible. This manuscript will highlight existing guidelines and our recommendations for hormone evaluation for male infertility and empiric therapies including multivitamins, estrogen receptor modulators (clomiphene), estrogen conversion blockers (anastrozole), and hormone replacement.

Utility of antioxidants during assisted reproductive techniques: an evidence based review

Assisted reproductive technology (ART) is a common treatment of choice for many couples facing infertility issues, be it due to male or female factor, or idiopathic. Employment of ART techniques, however, come with its own challenges as the in vitro environment is not nearly as ideal as the in vivo environment, where reactive oxygen species (ROS) build-up leading to oxidative stress is kept in check by the endogenous antioxidants system. While physiological amounts of ROS are necessary for normal reproductive function in vivo, in vitro manipulation of gametes and embryos exposes these cells to excessive ROS production either by endogenous or exogenous environmental factors. In this review, we discuss the sources of ROS in an in vitro clinical setting and the influence of oxidative stress on gamete/embryo quality and the outcome of IVF/ICSI. Sources of ROS and different strategies of overcoming the excessive generation of ROS in vitro are also highlighted. Endogenously, the gametes and the developing embryo become sources of ROS. Multiple exogenous factors act as potential sources of ROS, including exposure to visible light, composition of culture media, pH and temperature, oxygen concentration, centrifugation during spermatozoa preparation, ART technique involving handling of gamete/embryo and cryopreservation technique (freeze/thawing process). Finally, the use of antioxidants as agents to minimize ROS generation in the in vitro environment and as oral therapy is highlighted. Both enzymatic and non-enzymatic antioxidants are discussed and the outcome of studies using these antioxidants as oral therapy in the male or female or its use in vitro in media is presented. While results of studies using certain antioxidant agents are promising, the current body of evidence as a whole suggests the need for further well-designed and larger scale randomized controlled studies, as well as research to minimize oxidative stress conditions in the clinical ART setting.

The importance of the one carbon cycle nutritional support in human male fertility: a preliminary clinical report

BACKGROUND

Sperm chromatin structure is often impaired; mainly due to oxidative damage. Antioxidant treatments do not consistently produce fertility improvements and, when given at high doses, they might block essential oxidative processes such as chromatin compaction. This study was intended to assess the effect on male sub-fertility of a pure one carbon cycle nutritional support without strong antioxidants.

METHODS

Male partners of couples resistant to at least 2 assisted reproductive technology (ART) attempts, with no evidence of organic causes of infertility and with either DNA fragmentation index (DFI) measured by Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) or nuclear decondensation index (SDI) measured by aniline blue staining exceeding 20%, were invited to take part in a trial of a nutritional support in preparation for a further ART attempt. The treatment consisted of a combination of B vitamins, zinc, a proprietary opuntia fig extract and small amounts of N-acetyl-cysteine and Vitamin E (Condensyl™), all effectors of the one carbon cycle.

RESULTS

84 patients were enrolled, they took 1 or 2 Condensyl™ tablets per day for 2 to 12 months. Positive response rates were 64.3% for SDI, 71.4% for DFI and 47.6% for both SDI and DFI. Eighteen couples (21%) experienced a spontaneous pregnancy before the planned ART cycle, all ended with a live birth. The remaining 66 couples underwent a new ART attempt (4 IUI; 18 IVF; 44 ICSI) resulting in 22 further clinical pregnancies and 15 live births. The clinical pregnancy rate (CPR) and the live birth rate (LBR) were 47.6% and 39.3% respectively. The full responders, i.e. the 40 patients achieving an improvement of both SDI and DFI, reported a CPR of 70% and a LBR of 57.5% (p<0.001).

CONCLUSIONS

Nutritional support of the one carbon cycle without strong antioxidants improves both the SDI and the DFI in ART resistant male partners and results in high pregnancy rates suggesting a positive effect on their fertility potential.

Antioxidants for male subfertility

BACKGROUND

Between 30% to 80% of male subfertility cases are considered to be due to the damaging effects of oxidative stress on sperm and 1 man in 20 will be affected by subfertility. Antioxidants are widely available and inexpensive when compared to other fertility treatments and many men are already using these to improve their fertility. It is thought that oral supplementation with antioxidants may improve sperm quality by reducing oxidative stress. Pentoxifylline, a drug that acts like an antioxidant, was also included in this review.  

OBJECTIVES

This Cochrane review aimed to evaluate the effectiveness and safety of oral supplementation with antioxidants for subfertile male partners in couples seeking fertility assistance.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO and AMED databases (from inception until January 2014); trial registers; sources of unpublished literature and reference lists. An updated search was run in August 2014 when potentially eligible studies were placed in 'Studies awaiting assessment'.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing any type or dose of antioxidant supplement (single or combined) taken by the subfertile male partner of a couple seeking fertility assistance with a placebo, no treatment or another antioxidant.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible studies, extracted the data and assessed the risk of bias of the included studies. The primary review outcome was live birth; secondary outcomes included clinical pregnancy rates, adverse events, sperm DNA fragmentation, sperm motility and concentration. Data were combined, where appropriate, to calculate pooled odds ratios (ORs) or mean differences (MD) and 95% confidence intervals (CIs). Statistical heterogeneity was assessed using the I(2) statistic. We assessed the overall quality of the evidence for the main outcomes using GRADE methods.  

MAIN RESULTS

This updated review included 48 RCTs that compared single and combined antioxidants with placebo, no treatment or another antioxidant in a population of 4179 subfertile men. The duration of the trials ranged from 3 to 26 weeks with follow up ranging from 3 weeks to 2 years. The men were aged from 20 to 52 years. Most of the men enrolled in these trials had low total sperm motility and sperm concentration. One study enrolled men after varicocelectomy, one enrolled men with a varicocoele, and one recruited men with chronic prostatitis. Three trials enrolled men who, as a couple, were undergoing in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) and one trial enrolled men who were part of a couple undergoing intrauterine insemination (IUI). Funding sources were stated by 15 trials. Four of these trials stated that funding was from a commercial source and the remaining 11 obtained funding through non-commercial avenues or university grants. Thirty-three trials did not report any funding sources.A limitation of this review was that in a sense we had included two different groups of trials, those that reported on the use of antioxidants and the effect on live birth and clinical pregnancy, and a second group that reported on sperm parameters as their primary outcome and had no intention of reporting the primary outcomes of this review. We included 25 trials reporting on sperm parameters and only three of these reported on live birth or clinical pregnancy. Other limitations included poor reporting of study methods, imprecision, the small number of trials providing usable data, the small sample size of many of the included studies and the lack of adverse events reporting. The evidence was graded as 'very low' to 'low'. The data were current to 31 January 2014.Live birth: antioxidants may have increased live birth rates (OR 4.21, 95% CI 2.08 to 8.51, P< 0.0001, 4 RCTs, 277 men, I(2) = 0%, low quality evidence). This suggests that if the chance of a live birth following placebo or no treatment is assumed to be 5%, the chance following the use of antioxidants is estimated to be between 10% and 31%. However, this result was based on only 44 live births from a total of 277 couples in four small studies.Clinical pregnancy rate: antioxidants may have increased clinical pregnancy rates (OR 3.43, 95% CI 1.92 to 6.11, P < 0.0001, 7 RCTs, 522 men, I(2) = 0%, low quality evidence). This suggests that if the chance of clinical pregnancy following placebo or no treatment is assumed to be 6%, the chance following the use of antioxidants is estimated at between 11% and 28%. However, there were only seven small studies in this analysis and the quality of the evidence was rated as low.Miscarriage: only three trials reported on this outcome and the event rate was very low. There was insufficient evidence to show whether there was a difference in miscarriage rates between the antioxidant and placebo or no treatment groups (OR 1.74, 95% CI 0.40 to 7.60, P = 0.46, 3 RCTs, 247 men, I(2) = 0%, very low quality evidence). The findings suggest that in a population of subfertile men with an expected miscarriage rate of 2%, use of an antioxidant would result in the risk of a miscarriage lying between 1% and 13%.Gastrointestinal upsets: there was insufficient evidence to show whether there was a difference in gastrointestinal upsets when antioxidants were compared to placebo or no treatment as the event rate was very low (OR 1.60, 95% CI 0.47 to 5.50, P = 0.46, 6 RCTs, 429 men, I(2) = 0%).We were unable to draw any conclusions from the antioxidant versus antioxidant comparison as not enough trials compared the same interventions.

AUTHORS' CONCLUSIONS

There is low quality evidence from only four small randomised controlled trials suggesting that antioxidant supplementation in subfertile males may improve live birth rates for couples attending fertility clinics. Low quality evidence suggests that clinical pregnancy rates may increase. There is no evidence of increased risk of miscarriage but this is uncertain as the evidence is of very low quality. Data were lacking on other adverse effects. Further large well-designed randomised placebo-controlled trials are needed to clarify these results.