The probable destructive mechanisms behind COVID-19 on male reproduction system and fertility

Investigating the effects of the Omicron variant of COVID-19 on sperm parameters and serum levels of male sexual hormones: Prospective observational study

Background

With the progress and prevalence of COVID-19, concerns have arisen regarding its impact on men's sexual health. Therefore, this study was conducted with the aim of examining the effects of COVID-19 on serum levels of sex hormones and semen.

Methods

Sixty participants who met the study inclusion criteria enrolled in this study between January and April 2022. The individuals were divided into three groups (n = 20): healthy, COVID-19 positive, and recovered from COVID-19. Blood and semen samples were collected from the participants. Serum levels of sex hormones and semen were evaluated both macroscopically and microscopically.

Results

Our study results showed that the most common symptoms observed in the COVID-19 group were cough (100 %), fever (100 %), fatigue (95 %), and runny nose (90 %). Serum levels of sex hormones (testosterone, FSH, and prolactin) in the COVID-19 group were significantly decreased compared to the healthy group. Microscopic examination of semen revealed significant differences in vitality, progressive, and motile parameters among the three groups, with a decrease observed in the COVID-19 group.

Conclusion

These results indicate that COVID-19 may have a negative impact on men's sexual health, potentially affecting hormone production and sperm quality. Further research is needed to determine the long-term effects of COVID-19 on male fertility and to explore potential treatment options.

Cuproptosis mediates copper-induced testicular spermatogenic cell death

Cuproptosis, a novel mechanism of programmed cell death, has not been fully explored in the context of spermatogenic cells. This study investigated the potential involvement of cuproptosis in spermatogenic cell death using a mouse model of copper overload. Sixty male Institute of Cancer Research (ICR) mice were randomly divided into four groups that received daily oral gavage with sodium chloride (control) or copper sulfate (CuSO4) at 50 mg kg-1, 100 mg kg-1, or 200 mg kg-1, for 42 consecutive days. Mice subjected to copper overload exhibited a disruption in copper homeostasis. Additionally, significant upregulated expression of key cuproptosis factors was accompanied by a significant rise in the rates of testicular tissue cell apoptosis. Immunohistochemical analysis revealed the presence of ferredoxin 1 (Fdx1) in Sertoli cells, Leydig cells, and spermatogenic cells at various stages of testicular development, and the Fdx1-positive staining area was significantly increased in copper-overloaded mice. Mitochondrial dysfunction and decreased adenosine triphosphate levels were also observed, further implicating mitochondrial damage under cuproptosis. Further analyses revealed pathological lesions and blood-testis barrier destruction in the testicular tissue, accompanied by decreased sperm concentration and motility, in copper-overloaded mice. In summary, our results indicate that copper-overloaded mice exhibit copper homeostasis disorder in the testicular tissue and that cuproptosis participates in spermatogenic cell death. These findings provide novel insights into the pathogenic mechanisms underlying spermatogenic cell death and provide initial experimental evidence for the occurrence of cuproptosis in the testis.

Impact of COVID-19 disease on the male factor in reproductive medicine - how-to advise couples undergoing IVF/ICSI

CONTEXT

The COVID-19 pandemic has caused widespread concern about its potential impact on various aspects of human health.

AIMS

This narrative review aims to summarise the current knowledge about the impact of COVID-19 on sperm quality and its effect on assisted reproductive technology.

METHODS

In this narrative review, a literature search using the PubMed and MEDLINE databases was conducted to identify relevant original research articles published up to 29 January 2023.

RESULTS

Thirty original studies were included in our review. There is evidence that SARS-CoV-2 is detectable in seminal fluid during the acute phase of infection and for up to 1month. However, the fact that SARS-CoV-2 is barely detectable in semen makes sexual transmission very unlikely. COVID-19 infection has been associated with the following changes in sperm quality: morphology, altered motility, changed DNA fragmentation-index (DFI), decreased sperm concentration, lower total number of sperm, and a significant increase in leukocytes and cytokines. The effects mostly seem to be reversible and have not been shown to negatively affect the outcome of assisted reproductive technology but should lead to further research concerning the health of the offspring, because a correlation of increased DFI after COVID-19 even 5months after disease could be assumed.

CONCLUSIONS

The findings of this narrative review suggest that SARS-CoV-2 may harm sperm quality in the acute phase.

IMPLICATIONS

A recovery time of at least 3months regarding assisted reproductive therapy could be reasonable.

The influence of SARS-CoV-2 on male reproduction and men's health

BACKGROUND

SARS-CoV-2, the virus responsible for COVID-19, primarily affects the respiratory system by targeting the Angiotensin-converting enzyme 2 (ACE2) receptor and TMPRSS2. However, these receptors are also present in other organs, including the testes, where a higher concentration of ACE2 receptors has been observed. This raises concerns about the potential impact of the virus on male fertility.

AIMS

In this study, we aimed to assess the effects of SARS-CoV-2 on semen parameters by comparing samples during and after infection in the same patients.

MATERIALS & METHOD

The study enrolled 51 individuals who had contracted COVID-19 and analysed various parameters related to sperm quality and quantity, including C-reactive protein, testosterone levels, total sperm concentration, motility and morphology. A comparison was made between these parameters during the initial infection with SARS-CoV-2 and after a 2- and 5-month recovery period.

RESULTS

The results indicated that all of the mentioned parameters were significantly affected during COVID-19 infection (PCR-ct, CRP, WBCs LH, FSH and testosterone levels, p-value = .0001). Furthermore, the study assessed TC, TM and sperm morphology in patients infected with SARS-CoV-2 and found that these parameters were also significantly influenced during the infection, (p-value = .0001; Morphology, p-value = .0004). We observed significant alterations in sperm count and morphology during infection, suggesting a potential negative impact on sperm quality. Additionally, lower hormone levels were observed during COVID-19 infection, possibly due to increased inflammatory cytokines. However, both hormones and inflammation markers returned to normal following recovery. Our findings indicate a statistically significant change in total sperm count, motility and morphology post-infection, which aligns with previous studies. Discussion, COVID-19 have a transient impact on sperm parameters and fertility, emphasizing the importance of further investigation into the long-term implications.

[Infections and male infertility]

BACKGROUND

The role of urogenital infections in male infertility has long been the subject of debate.

METHODS

A bibliographic search limited to English-language literature on human subjects published before 5/2023 resulted in the selection of 189 articles.

RESULTS

Male infertility is often of multifactorial aetiology, and to optimise the prognosis it is important to manage all the factors that can be corrected, including infectious causes, which represent one of the most frequent aetiologies. The infectious agents involved in urogenital infections are most often bacterial or viral, and more rarely parasitic. They can infect the seminal tract, male accessory glands and/or testicles, and usually result in inflammation and increased oxidative stress. These infections reduce male fertility, in particular by altering spermogram parameters and increasing sperm DNA fragmentation. For these reasons, the search for a urogenital infection should be systematic, involving a careful history and clinical examination, ultrasound and systematic bacteriological tests guided by clinical findings. Aetiological treatment may be proposed depending on the picture and the germ involved.

CONCLUSION

This review should help the urologist to establish an accurate diagnosis of the form and extent of the infection, and enable him to define an appropriate therapeutic strategy, tailored to the patient, in order to obtain the best chances of improving male fertility.

Comparison of testosterone, FSH, LH and E2 hormone levels in infertility suspected males with COVID-19 infection

BACKGROUND

Coronavirus disease 2019 (COVID-19) is an infectious disease that has many adverse impacts on many systems including reproduction. The direct effects of COVID-19 on urogenital system are still open to argue. This study aimed to compare testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) hormone levels in COVID-19 infected male individuals with infertility suspicion.

METHODS

One hundred five control (healthy) and 105 COVID-19 infected males aged between 20 to 54 years old were enrolled in the study. All patients were either diagnosed with primary or secondary infertility suspicion. The COVID-19 infection was diagnosed via reverse-transcription polymerase chain reaction test. Blood samples from patients were analyzed from the control and COVID-19 group to measure serum testosterone, FSH, LH, and E2 levels. Hormone levels were statistically compared between groups with the Independent T test.

RESULTS

In control and COVID-19 patients, no significance was determined for FSH and LH hormone values. Testosterone hormone were significantly decreased and E2 level was statistically increased in COVID-19 patients compared to that in the control group (P < .001).

CONCLUSION

COVID-19 is a viral disease that affects organ including gonads. COVID-19 infection decreased testosterone levels and increased E2 levels, which leading to disorders in male and female reproductivity.

A systematic review of the effect of COVID-19 on semen parameters

Background and objectives

Since the outbreak of COVID-19, more and more studies have proved that it has an impact on the male reproductive system. The purpose of this article is to investigate the effects of COVID-19 on male semen parameters, further analyze the incidence and risk factors of diseases related to semen parameters, and put forward to corresponding preventive measures.

Methods

Retrieved from PubMed, Embase, The Cochrane Library, Web of Science, Clinicaltrails, CNKI, CBM, Wanfang Database and VIP to collect research on the effects of COVID-19 on the male reproductive system. The literature search was conducted until January 2022. In strict accordance with the inclusion and exclusion criteria, two researchers independently screened the literature and comprehensively analyzed five cohort studies on the impact of COVID-19 on male reproductive system. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the included cohort studies, and Revman 5.4.1 was applied for statistical analysis.

Results

Semen volume (RR = −0.10; 95% CI: 0.45, 0.26; P = 0.60), there was no significant difference between the test group and the control group; Sperm count (RR = −45.28; 95% CI: 66.38, 24.19; P = 0.0001), the sperm count of the COVID-19 test group was lower than that of the control group, and the difference was statistically significant; Sperm concentration (RR = −15.65 × 106; 95%CI: 31.52 × 106, 0.21 × 106; P = 0.05), there was no significant difference between the test group and the control group; progressive sperm motility (RR = 4.31; 95% CI: 4.62, 13.24; P = 0.34), there was no effect on progressive sperm motility in the COVID-19 test group compared with the control group.

Conclusions

COVID-19 can reduce semen quality and affect male fertility. However, due to the limitations of this study, this conclusion needs to be further verified by large-sample, high-quality prospective cohort studies on the long-term effects of COVID-19 on male reproductive function.

SARS-CoV-2 infection and multi-organ system damage: A review

The SARS-CoV-2 infection causes COVID-19, which has affected approximately six hundred million people globally as of August 2022. Organs and cells harboring angiotensin-converting enzyme 2 (ACE2) surface receptors are the primary targets of the virus. However, once it enters the body through the respiratory system, the virus can spread hematogenously to infect other body organs. Therefore, COVID-19 affects many organs, causing severe and long-term complications, even after the disease has ended, thus worsening the quality of life. Although it is known that the respiratory system is most affected by the SARS-CoV-2 infection, many organs/systems are affected in the short and long term. Since the COVID-19 disease simultaneously affects many organs, redesigning diagnostic and therapy policies to fit the damaged organs is strongly recommended. Even though the pathophysiology of many problems the infection causes is unknown, the frequency of COVID-19 cases rises with age and the existence of preexisting symptoms. This study aims to update our knowledge of SARS-CoV-2 infection and multi-organ dysfunction interaction based on clinical and theoretical evidence. For this purpose, the study comprehensively elucidates the most recent studies on the effects of SARS-CoV-2 infection on multiple organs and systems, including respiratory, cardiovascular, gastrointestinal, renal, nervous, endocrine, reproductive, immune, and parts of the integumentary system. Understanding the range of atypical COVID-19 symptoms could improve disease surveillance, limit transmission, and avoid additional multi-organ-system problems.

Infection of SARS-CoV-2 causes severe pathological changes in mouse testis

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected more than 600 million people worldwide. Several organs including lung, intestine, and brain are infected by SARS-CoV-2. It has been reported that SARS-CoV-2 receptor angiotensin-converting enzyme-2 (ACE2) is expressed in human testis. However, whether testis is also affected by SARS-CoV-2 is still unclear. In this study, we generate a human ACE2 (hACE2) transgenic mouse model in which the expression of hACE2 gene is regulated by hACE2 promoter. Sertoli and Leydig cells from hACE2 transgenic mice can be infected by SARS-CoV-2 pseudovirus in vitro, and severe pathological changes are observed after injecting the SARS-CoV-2 pseudovirus into the seminiferous tubules. Further studies reveal that Sertoli and Leydig cells from hACE2 transgenic mice are also infected by authentic SARS-CoV-2 virus in vitro. After testis interstitium injection, authentic SARS-CoV-2 viruses are first disseminated to the interstitial cells, and then detected inside the seminiferous tubules which in turn cause germ cell loss and disruption of seminiferous tubules. Our study demonstrates that testis is most likely a target of SARS-CoV-2 virus. Attention should be paid to the reproductive function in SARS-CoV-2 patients.

Epigenetics Role in Spermatozoa Function: Implications in Health and Evolution-An Overview

The unique properties of spermatozoa are established through the spermatogenesis and maturation processes concurrently with its epigenome. It is known that damage to epigenetic mechanisms can lead to reproductive problems. However, scientific reviews addressing the role of the spermatozoa epigenome during the reproductive process are scarce. Therefore, the aim of this review was to offer a detailed overview of current knowledge in the field of spermatozoa epigenetics and its consequent implications. A full search was performed through three databases by combining five keywords. Inclusion criteria were implemented to grant accessibility, relevance, and concretion. Besides, some articles were manually removed or added to obtain an adequate and complete collection of 485 scientific publications. This compilation was used to conduct the bibliometric analysis and the data review separately. Bibliometric results displayed that spermatozoa epigenetics is an active and growing research area. The bibliographic overview showed that sperm epigenome correlates with the development of its function, explaining the environmental influence on reproductive pathologies or abnormal inheritance. The main conclusions were that the normal performance of sperm is heavily reliant on its epigenetics and that this study area is burgeoning, with the potential ability to provide society with clinical innovations in a short-term period.

Semen Quality in Males Suffering From COVID-19: A Pilot Study

Background It is well known that some viral infections may affect male fertility. Coronavirus disease (COVID-19) can lead to multiorgan damage through the angiotensin-converting enzyme-2 receptor, abundant in testicular tissue. However, little information is available regarding the shedding of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in semen and its impact on spermatogenesis and fertility potential. We planned to investigate the presence of SARS-CoV-2 in the semen of COVID-19 males and to study the effect of COVID-19 on semen quality and sperm DNA fragmentation index. Material and method Thirty COVID-19 male patients aged 19-45 registered to AIIMS Patna hospital participated in the survey between October 2020 and April 2021. We conducted a real-time reverse transcriptase test on all the semen samples. Detailed semen analysis, including the sperm DNA Fragmentation Index, was done at first sampling that is during COVID-19. After 74 days of the first sampling, we obtained the second sampling and repeated all the above tests. Results All semen samples collected in the first and second sampling tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) were negative for SARS-CoV-2. In the first sampling, semen volume, vitality, total motility, sperm concentration, total sperm count, % normal morphology, % cytoplasmic droplet, and fructose were significantly lower. In contrast, semen agglutination, % head defect, DNA Fragmentation Index, liquefaction time, semen viscosity, and leukocytes were increased. These findings were reversed at the second sampling but not to the optimum level. All these findings were statistically significant (p < 0.05 for all). Thus, COVID-19 negatively affects semen parameters, including sperm DNA fragmentation index. Conclusion Although we could not find SARS-CoV-2 in the semen, the semen quality remained poor until the second sampling. Assisted reproductive technology (ART) clinics and sperm banking facilities should consider assessing the semen of COVID-19 males and exclude men with a positive history of SARS-CoV-2 until their semen quality returns to normal.

Tomato spotted wilt orthotospovirus shifts sex ratio toward males in the western flower thrips, Frankliniella occidentalis, by down-regulating a FSCB-like gene

BACKGROUND

Plant viruses can facilitate their transmission by modulating the sex ratios of their insect vectors. Previously, we found that exposure to tomato spotted wilt orthotospovirus (TSWV) in the western flower thrips, Frankliniella occidentalis, led to a male-biased sex ratio in the offspring. TSWV, a generalist pathogen with a broad host range, is transmitted primarily by F. occidentalis in a circulative-propagative manner. Here, we integrated proteomic tools with RNAi to comprehensively investigate the genetic basis underlying the shift in vector sex ratio induced by the virus.

RESULTS

Proteomic analysis exhibited 104 differentially expressed proteins between F. occidentalis adult males with and without TSWV. The expression of the fiber sheath CABYR-binding-like (FSCB) protein, namely FoFSCB-like, a sperm-specific protein associated with sperm capacitation and motility, was decreased by 46%. The predicted FoFSCB-like protein includes 10 classic Pro-X-X-Pro motifs and 42 phosphorylation sites, which are key features for sperm capacitation. FoFSCB-like expression was gradually increased during the development and peaked at the pupal stage. After exposure to TSWV, FoFSCB-like expression was substantially down-regulated. Nanoparticle-mediated RNAi substantially suppressed FoFSCB-like expression and led to a significant male bias in the offspring.

CONCLUSION

These combined results suggest that down-regulation of FoFSCB-like in virus-exposed thrips leads to a male-biased sex ratio in the offspring. This study not only advances our understanding of virus-vector interactions, but also identifies a potential target for the genetic management of F. occidentalis, the primary vector of TSWV, by manipulating male fertility. © 2022 Society of Chemical Industry.

Spike protein of SARS-CoV-2 suppresses gonadotrophin secretion from bovine anterior pituitaries

Coronavirus disease (COVID-19), the ongoing global pandemic, is caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Recent evidence shows that the virus utilizes angiotensin-converting enzyme 2 (ACE2) as a spike protein receptor for entry into target host cells. The bovine ACE2 contains key residues for binding to the spike protein receptor-binding domain. This study evaluated the hypothesis that bovine gonadotroph expresses ACE2, and spike protein suppresses luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion from cultured bovine anterior pituitary (AP) cells. ACE2 mRNA expression and ACE2 protein expression were detected in the bovine AP cells using reverse transcription PCR and western blot analysis. Immunofluorescence microscopy analysis with the anti-ACE2 antibody revealed the co-localization of ACE2 and gonadotropin-releasing hormone (GnRH) receptor on the gonadotroph plasma membrane. Approximately 90% of GnRH receptor-positive cells expressed ACE2, and approximately 46% of ACE2-positive cells expressed the GnRH receptor. We cultured bovine AP cells for 3.5 days and treated them with increasing concentrations (0, 0.07, 0.7, or 7 pM) of recombinant spike protein having both S1 and S2 regions. The spike protein (0.07-7 pM) suppressed both basal and GnRH-induced LH secretion (P < 0.05). Spike protein (0.7-7 pM) suppressed GnRH-induced (P < 0.05), but not basal FSH secretion. In contrast, pre-treatment with ERK 1/2/5 inhibitor (U0126) partially restored the GnRH-induced LH and FSH secretion from the spike protein suppression. Collectively, the results indicate that gonadotrophs express ACE2, a receptor for coronavirus 2 spike protein, which in turn suppresses LH and FSH secretion from AP cells.

Effects of Different Drug Therapies and COVID-19 mRNA Vaccination on Semen Quality in a Man with Ankylosing Spondylitis: A Case Report

Background and Objectives: Ankylosing spondylitis (AS) is a condition that affects 0.1% to 0.5% of the adult population. The aim of this case report was to investigate the possible effects of the drugs taken for treatment of AS as well as mRNA vaccination for COVID-19 on semen quality by performing a highly detailed analysis. Materials and Methods: Sperm characteristics were examined by light microscopy, DNA fragmentation (DFI) was analysed by flow cytometry and morphology was evaluated by transmission electron microscopy (TEM). Results: Semen analysis under therapy with (1) celecoxib and sulphasalazine showed: concentration 47 million/mL, 53% progressive motility, 7% normal morphology and 9.6% DFI, (2) Golimumab and before mRNA Vaccination showed: concentration 108 million/mL, 82% progressive motility, 1% normal morphology and 7.6% DFI, and (3) Golimumab and after 3 doses of mRNA Vaccination showed: concentration 142 million/mL, 85% progressive motility, 1% normal morphology and 6.8% DFI. TEM revealed head, neck and tail abnormalities, as well as the presence of cells with incomplete spermiogenesis white cells and phagocytes in the sample under therapy with celecoxib and sulphasalazine. Golimumab treatment lead to an increased incidence of elongated heads but in general reduced inflammation as no white cells were evident in TEM. Conclusion: The anti-inflamatory drugs celecoxib and sulphasalazine had no adverse effect on sperm quality as all parameters were within normal limits and the patient achieved under that treatment 2 pregnancies following natural conception that lead to the birth of a healthy boy and girl respectively. Anti-TNFa treatment with Golimumab exerted a negative effect on morphology but not on concentration, motility and DFI. After 3 doses of mRNA Vaccination, sperm concentration increased while motility, morphology and DFI remained similar to the values before vaccination suggesting no negative effect of the mRNA vaccine for COVID-19 on sperm quality.

Evaluation of SARS-CoV-2 in semen, seminal plasma, and spermatozoa pellet of COVID-19 patients in the acute stage of infection

To date, there is limited information about the presence of SARS-CoV-2 in semen especially in the acute phase of the infection. While available data from cohort studies including a total of 342 patients in the acute or recovery phase of the infection are reassuring, one study mentioned detecting virus in the semen of 6/38 COVID-19 patients. Here we assessed SARS-CoV-2 presence in the semen of COVID-19 positive patients in the acute stage of infection, within 24 hours of the positive nasopharyngeal swabs. Semen, seminal plasma and spermatozoa pellet were screened for SARS-CoV-2 and manual or airborne contamination during semen sampling. Among the 32 COVID-19 volunteers, the median interval from the onset of symptoms to semen collection was 4 days [IQR: 0-8]. Only one presented positive SARS-CoV-2 PCR in semen and seminal plasma fractions, although the spermatozoa pellet was negative. Viral cultures were all negative. We observed slightly higher concentrations of bacterial DNA in the SARS-CoV-2 positive specimen than in all negative samples. The bacteria identified neither confirm nor rule out contamination by oropharyngeal secretions during collection. SARS-CoV-2 was rarely present in semen during the acute phase of the disease. This very rare situation could be connected to oral or manual contamination during semen collection. The possible presence of SARS-CoV-2 in semen calls for nasopharyngeal viral testing and strict hygiene protocols during semen collection before assisted reproductive attempts.

Potential effects of COVID-19 on reproductive health: a mini review

Coronavirus disease 2019 (COVID-19) is now a major public health problem worldwide. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity is extremely strong. One major target of the virus is the lung, which can lead to death due to the development of respiratory distress syndrome and even multiple system organ failure. The possible pathophysiology by which SARS-CoV-2 affects the object is by way of the receptor, angiotensin-converting enzyme 2 (ACE2). From the study of the viral structure and infection mechanisms, researchers have discovered that the ACE2 acts as a receptor for SARS-CoV-2. According to previous studies, ACE2 is one of the key enzymes in the RAS system. Physiological functions can be found in angiosarcomas and in the kidney, liver, intestine and so on. Whether SARS-CoV-2 infection leads to male fertility impairment has recently received attention. Nevertheless, the association between SARS-CoV-2 infection and reproductive health is currently poorly understood. Using key words including "SARS-CoV-2", "reproductive health", "ACE2" and "2019-nCoV", we retrieved original articles and reviews from the PubMed and WEB OF SCI databases published before December 16, 2020 and performed a thorough review of them. Compared with females, we discovered that infected person with SARS-CoV-2 was higher in males. Men who were infected with SARS-CoV-2 may be easy to suffer from impaired reproductive health. These investigations would help for a comprehensive grasp of the relationship between SARS-CoV-2 infection and reproductive health.

Air Pollution and COVID-19: A Possible Dangerous Synergy for Male Fertility

Several studies indicate that semen quality has strongly declined in the last decades worldwide. Air pollution represents a significant co-factor with the COVID-19 impact and has negative effects on the male reproductive system, through pro-oxidant, inflammatory and immune-dysregulating mechanisms. It has recently been reported that chronic exposure to PM2.5 causes overexpression of the alveolar ACE2 receptor, the entry route of SARS-CoV-2 into the organism shared by the lungs and testis where expression is highest in the body. In the testis, the ACE2/Ang-(1-7)/MasR pathway plays an important role in the regulation of spermatogenesis and an indirect mechanism of testicular damage could be due to the blockade of the ACE2 receptor by SARS-CoV-2. This prevents the conversion of specific angiotensins, and their excess causes inflammation with the overproduction of cytokines. PM2.5-induced overexpression of the alveolar ACE2 receptor, in turn, could increase local viral load in patients exposed to pollutants, producing ACE2 receptor depletion and compromising host defenses. By presenting an overall view of epidemiological data and molecular mechanisms, this manuscript aims to interpret the possible synergistic effects of both air pollution and COVID-19 on male reproductive function, warning that the spread of SARS-CoV-2 in the fertile years may represent a significant threat to global reproductive health. All of this should be of great concern, especially for men of the age of maximum reproductive capacity, and an important topic of debate for policy makers. Altered environmental conditions, together with the direct and indirect short- and long-term effects of viral infection could cause a worsening of semen quality with important consequences for male fertility, especially in those areas with higher environmental impact.