Impact of the SARS-CoV-2 virus on male reproductive health.

The coronavirus 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to more than 160 million infections and 3.5 million deaths globally. Men are disproportionately affected by COVID-19, having more severe disease with higher mortality rates than women. Androgens have been implicated as the underlying cause for more severe disease, as the androgen receptor has been noted to upregulate the cell surface receptors that mediate viral cell entry and infection. Unfortunately, despite testosterone's potential role in COVID-19 prognosis, androgen deprivation therapy is neither protective nor a treatment for COVID-19. Interestingly, the male reproductive organs have been found to be vulnerable in moderate to severe illness, leading to reports of erectile dysfunction and orchitis. COVID-19 viral particles have been identified in penile and testis tissue, both in live patients who recovered from COVID-19 and post mortem in men who succumbed to the disease. Although sexual transmission remains unlikely in recovered men, moderate to severe COVID-19 infection can lead to germ cell and Leydig cell depletion, leading to decreased spermatogenesis and male hypogonadism. The objective of this review is to describe the impact of SARS-CoV-2 on male reproductive health. There are still many unanswered questions as to the specific underlying mechanisms by which COVID-19 impacts male reproductive organs and the long-term sequelae of SARS-CoV-2 on male reproductive health.

Platelet Rich Plasma (PRP) Growth Factor Concentration Varies in Men With Erectile Dysfunction.

BACKGROUND: Platelet Rich Plasma (PRP) is a novel therapy rich in growth factors and cytokines used to target the underlying causes of erectile dysfunction (ED). It is not known, however, if the composition of growth factors in PRP varies between men. AIM: To evaluate PRP growth factor variability among men with ED. METHODS: Whole blood was collected from 8 participants with at least a 6-month history of ED. Seven men with Peyronie's disease and 1 healthy male (without sexual dysfunction) were used as the control group. PRP was extracted from whole blood using the Arthrex Angel system. A Human Growth Factor Antibody Array for 41 proteins was performed using 3 participants and the healthy control. Using all 16 samples, quantitative detection of factors from the array that were decreased by 1.5-fold were validated with western blot. OUTCOMES: From the growth factor array, 2 growth factors-granulocyte-macrophage colony stimulating factor and transforming growth factor-ß were identified as having a 1.5-fold decrease between the participants and the control. Vascular endothelial growth factor (VEGF) was selected because androgens can upregulate VEGF production. Other than a weak negative correlation between VEGF expression and age, we found no correlation between growth factor expression for granulocyte-macrophage colony stimulating factor or transforming growth factor-ß and age, body mass index, or comorbidities. CLINICAL TRANSLATION: PRP growth factor concentration appears to vary among men with ED. PRP treatment for ED may need to be personalized for patients, depending on individual growth factor concentration. STRENGTHS AND LIMITATIONS: This study demonstrates the variability in PRP growth factors among men with ED. This is an important finding in the investigation of PRP as a restorative treatment option for men with ED. Our study, however, was limited by a small sample size. CONCLUSION: PRP growth factors vary among men with ED. Khodamoradi K, Dullea A, Golan R, et al. Platelet Rich Plasma (PRP) Growth Factor Concentration Varies in Men With Erectile Dysfunction. J Sex Med 2022;19:1488-1493.

Fear about adverse effect on fertility is a major cause of COVID-19 vaccine hesitancy in the United States.

Although COVID-19 vaccine access has increased nationwide, vaccination rates have been slow-moving, with many studies showing significant vaccine hesitancy in the U.S. We conducted an online survey using Amazon Mechanical Turk (MTurk) to identify reasons for vaccine hesitancy among unvaccinated adults between June 30 and July 1, 2021. We found that 58% of unvaccinated respondents were worried about unknown long-term adverse effects. Of these, 41% believed that the COVID-19 vaccines can negatively impact reproductive health and or fertility, and 38% were unsure of the effects on fertility. Our study demonstrates that fear regarding COVID-19 vaccine adverse effects and belief that they can negatively impact fertility is a major cause of vaccine hesitancy in the United States. We identified that urban residents, married individuals, those born outside the U.S., those with health insurance, and people with higher education and income greater than $100,000 felt that the vaccine would affect fertility more than their counterparts did. Finally, we found that 48% of unvaccinated respondents cited 'more information and research conducted on the COVID-19 vaccines' as the action that would most encourage vaccine uptake.

COVID-19 vaccination not associated with increased risk of erectile dysfunction.

Although mRNA COVID-19 vaccines have proven to be safe and effective against SARS-CoV-2, vaccination rates have slowed, with some individuals citing impotence as a concern. Therefore, we conducted a survey of the US males to evaluate the impact of COVID-19 vaccination on erectile function. We hypothesized that vaccinated men would not have a higher risk of ED compared to unvaccinated men. Amazon Mechanical Turk (MTurk) was utilized to survey the US adult male population between August 26 and September 2, 2021. Survey participation was open to 1000 males over the age of 18 and currently living in the United States regardless of vaccination status or the past medical history of COVID-19. Selection criteria included respondents ≥45 years old, no history of physician-diagnosed ED, biologically born, and identify as male. Participants completed an anonymous 16-question survey that included a multidimensional scale used to evaluate ED, the International Index of Erectile Function (IIEF-5). Among vaccinated men, the median IIEF-5 score was 20 [16-24] compared to 22 [17.5-25] in the unvaccinated group (p = 0.195). The multivariable-adjusted analysis demonstrated that vaccination against COVID-19 was not associated with increased risk of ED. Overall, this cross-sectional survey showed that COVID-19 vaccination was not associated with an increased risk of erectile dysfunction in males 45 years and older.

Sperm cryopreservation and DNA methylation: possible implications for ART success and the health of offspring.

Despite the beneficial effects of sperm cryopreservation, increased reactive oxygen species (ROS) production during this process can affect spermatozoon structure and function. Moreover, ROS production is associated with elevated DNA damage and alterations in DNA methylation. There is little information about the effects of cryopreservation on epigenetic modulation in sperm and the health of children born with frozen spermatozoa. Considering the potential consequences of cryopreservation in ART-conceived children, it is necessary to assure that cryopreservation does not modify sperm DNA methylation status. This review summarizes reports on epigenetic modifications of spermatozoa during cryopreservation and the probable effects of this process on offspring health. Contradictory results have reported the influence of sperm cryopreservation on DNA methylation in imprinted genes. Multiclinical studies with larger sample sizes under the same conditions of cryopreservation and DNA methylation analysis are needed to make any definitive conclusion about the effect of the cryopreservation process on sperm DNA methylation.

Evaluation of a re-engineered device for penile vibratory stimulation in men with spinal cord injury.

STUDY DESIGN: Cohort study OBJECTIVES: The purpose of this study was to evaluate the performance of a re-engineered device (Ferticare 2.0), which is replacing the previous standard (Ferticare 1.0) for penile vibratory stimulation in men with spinal cord injury. Most men with spinal cord injury are anejaculatory, requiring medical assistance to obtain their semen. Penile vibratory stimulation is generally recognized as the standard of care for semen retrieval in these anejaculatory men. SETTING: Major Research University in Miami, Florida, USA. METHODS: The Ferticare 2.0 device was applied to 15 men with spinal cord injury in a three-step protocol simulating normal use. Step 1: one device (2.5 mm amplitude, 100 Hz) was applied to the glans penis for 2 min. Step 2: If no ejaculation occurred, the amplitude was increased to 4.0 mm (100 Hz) and the device similarly applied. Step 3: If no ejaculation occurred, two devices, each 2.5 mm and 100 Hz were applied to the dorsum and frenulum of the glans penis. Participants at risk for autonomic dysreflexia were pretreated with sublingual nifedipine (20 mg), 15 min prior to stimulation. Blood pressure and other symptoms of autonomic dysreflexia were monitored. Participants answered a questionnaire about their experience with the device. RESULTS: Thirteen of 15 participants ejaculated with the device. No adverse events occurred. All participants commented they would recommend the device to other men with spinal cord injury. CONCLUSIONS: A re-engineered device, the Ferticare 2.0, is safe and effective for inducing ejaculation in men with spinal cord injury.

How defective spermatogenesis affects sperm DNA integrity.

Spermatogenesis is the essential process to maintain and promote male fertility. It is extraordinarily complex with many regulatory elements and numerous steps. The process involves several cell types, regulatory molecules, repair mechanisms and epigenetic regulators. Evidence has shown that fertility can be negatively impacted by reduced sperm DNA integrity. Sources of sperm DNA damage include replication errors and causes of DNA fragmentation which include abortive apoptosis, defective maturation and oxidative stress. This review outlines the process of spermatogenesis, spermatogonial regulation and sperm differentiation; additionally, DNA damage and currently studied DNA repair mechanisms in spermatozoon are also covered.

Overview of biological effects of Quercetin on ovary.

Over the last few decades, using natural products has been increased to treat different diseases. Today, great attention has been pointed toward the usage of natural products such as flavonoids, especially Quercetin (QUR), in the treatment of diseases. QUR as a natural antioxidant has been traditionally used to prevent or treat a variety of diseases such as cancer, cardiovascular disease, polycystic ovary syndrome (PCOS), obesity, chronic inflammation, and reproductive system dysfunction. Several studies demonstrated that QUR acts as an anti-inflammatory, anti-apoptotic, antioxidant, and anticancer agent. With this in view, in this study, we intended to describe an overview of the biological effects of QUR on the ovary. QUR improves the quality of oocytes and embryos. It affects the proliferation and apoptosis and decreases the oxidative stress in granulosa cells (GCs). Furthermore, QUR can be used as a complementary and alternative therapy in ovarian cancer and it has beneficial effects in the treatment of PCOS patients. It seems that QUR as a supplementary factor has different activities for the treatment of different disorders and it also has bidirectional activities. However, further investigations are needed for understanding the efficacy of QUR in the treatment and improvement of gynecological patients.

The role of leptin and obesity on male infertility.

PURPOSE OF REVIEW: Several studies suggest a strong association between leptin, obesity, and infertility with respect to the hypothalamic-pituitary-gonadal (HPG) axis, androgen regulation, and sperm production, but the direct mechanistic association between these is still largely unexplored. This review focuses on understanding the association between leptin, obesity, and male infertility. RECENT FINDINGS: Obesity is linked to fertility dysfunction in both genders. Obesity in men may affect their fertility by impaired spermatogenesis, reduced testosterone levels, erectile dysfunction, and poor libido by putatively targeting the HPG and hypothalamic-pituitary-adrenal axes. Leptin plays key roles in many metabolic functions, including reproduction. High concentrations of leptin have been found in infertile men with disorders affecting the testicular parenchyma, including nonobstructive azoospermia, oligozoospermia, and oligo-astheno-teratozoospermia. Additionally, serum leptin levels have negative associations with serum testosterone levels and sperm parameters and positive associations with serum follicle-stimulating hormone and luteinizing hormone levels and abnormal sperm morphology. SUMMARY: Excessive leptin production may be a significant contributor to the development of androgen insufficiency and reduced reproductive function in obese men. Understanding the relation between leptin, obesity, and reproduction may shed light on future targeted treatments for male infertility.

The effect of cryopreservation on DNA methylation patterns of the chromosome 15q11-q13 region in human spermatozoa.

Human sperm cryopreservation is a common technique which is used in assisted reproductive technologies. Despite the existence of evidence supporting the production of ROS and DNA fragmentation during sperm cryopreservation, there is little and equivocal information about the cryopreservation effects on methylation of imprinted genes and imprinting control regions. In this study, we have investigated the effects of cryopreservation on DNA methylation in promoter regions of SNURF-SNRPN and UBE3A imprinted genes, PWS-ICR and AS-ICR in the chromosome 15q11-q13 region. Semen samples from 10 healthy normozoospermic men were collected and each sample was divided into four equal aliquots: fresh, cryoprotectant, cryopreservation, and H2O2. We measured the ROS levels and DNA fragmentation using DCFH-DA and TUNEL assay respectively by flow cytometry. DNA methylation in promoter regions of SNURF-SNRPN and UBE3A imprinted genes, PWS-ICR and AS-ICR in the chromosome 15q11-q13 region were evaluated by quantitative methylation-specific PCR technique. Intracellular levels of ROS and percentage of TUNEL-positive spermatozoa significantly increased in cryopreservation group compared to fresh group. Exposure to cryoprotectant had no significant effect on ROS levels and DNA fragmentation. Neither cryopreservation nor exposure to cryoprotectant significantly affected DNA methylation of the selected gene regions. However, DNA fragmentation had positive correlation with DNA methylation of AS-ICR. In conclusion, based on our study, clinical use of sperm cryopreservation for fertility treatments appear to be safe in regard to DNA methylation in the chromosome 15q11-q13 region.

Evaluation of androgen receptor markers in erectile dysfunction.

BACKGROUND: Steroid hormones, such as testosterone, play a crucial role in modulating the development of male internal and external genitalia as well as secondary sex characteristics by binding to the androgen receptor. Once bound, androgen receptor operates as an inducible transcription factor, interacting with a multitude of co-regulators to initiate various downstream signaling pathways. The androgen saturation hypothesis posits that beyond a specific threshold, androgen receptor binding and functionality remain unaltered despite an increase in serum testosterone levels. OBJECTIVES: The objective of this study was to explore the expression of these proteins in penile tissue samples from men with severe erectile dysfunction to enhance our understanding of the influence of serum testosterone on androgen receptor function. MATERIALS AND METHODS: Patients undergoing surgical management for high-grade ED at our institution were invited to participate in the study. During inflatable penile prosthesis surgery, corpus cavernosum biopsy was obtained. Protein was extracted from each sample for western blot analysis which was probed with androgen receptor, heme oxygenase, inducible nitric oxide synthase, and phosphodiesterase type 5 antibodies with GAPDH for protein normalization. RESULTS: 12 men agreed to participate in this study. Serum testosterone levels were obtained from all participants on the morning of their surgery. The median testosterone level was 300.15 ng/dL. Our findings revealed a decrease in androgen receptor and inducible nitric oxide synthase expression at serum testosterone levels below 300 ng/dL (p = 0.022, 0.03). Similarly, hemeoxygenase and phosphodiesterase type 5 expression levels were significantly lower at serum T concentrations below 200 ng/dL (p = 0.017, 0.014). DISCUSSION AND CONCLUSION: These data showed a significant decrease in the expression of proteins downstream of the androgen receptor at lower serum T levels. This suggests a potential correlation between serum T concentration and androgen receptor signaling and supports a potential saturation value between 200 and 300 ng/dL.

Detection of microplastics in the human penis.

The proliferation of microplastics (MPs) represents a burgeoning environmental and health crisis. Measuring less than 5 mm in diameter, MPs have infiltrated atmospheric, freshwater, and terrestrial ecosystems, penetrating commonplace consumables like seafood, sea salt, and bottled beverages. Their size and surface area render them susceptible to chemical interactions with physiological fluids and tissues, raising bioaccumulation and toxicity concerns. Human exposure to MPs occurs through ingestion, inhalation, and dermal contact. To date, there is no direct evidence identifying MPs in penile tissue. The objective of this study was to assess for potential aggregation of MPs in penile tissue. Tissue samples were extracted from six individuals who underwent surgery for a multi-component inflatable penile prosthesis (IPP). Samples were obtained from the corpora using Adson forceps before corporotomy dilation and device implantation and placed into cleaned glassware. A control sample was collected and stored in a McKesson specimen plastic container. The tissue fractions were analyzed using the Agilent 8700 Laser Direct Infrared (LDIR) Chemical Imaging System (Agilent Technologies. Moreover, the morphology of the particles was investigated by a Zeiss Merlin Scanning Electron Microscope (SEM), complementing the detection range of LDIR to below 20 µm. MPs via LDIR were identified in 80% of the samples, ranging in size from 20-500 µm. Smaller particles down to 2 µm were detected via SEM. Seven types of MPs were found in the penile tissue, with polyethylene terephthalate (47.8%) and polypropylene (34.7%) being the most prevalent. The detection of MPs in penile tissue raises inquiries on the ramifications of environmental pollutants on sexual health. Our research adds a key dimension to the discussion on man-made pollutants, focusing on MPs in the male reproductive system.

Androgen Receptor Signaling is Similar in Human Corpus Cavernosum in Men with Different Serum Testosterone Levels.

BACKGROUND: Testosterone (T) plays an important role in male reproductive function and tissue development. Normal serum T levels vary between 300 and 1000 ng/dl. It is not known, however, if varying serum T levels alter androgen receptor (AR) signaling in tissue. OBJECTIVE: To measure AR signaling levels in human corpus cavernosal tissue in males with different serum T levels. DESIGN, SETTING, AND PARTICIPANTS: Participants were selected from a group of males undergoing surgical management for erectile dysfunction (ED; penile prosthesis placement). T levels were measured 1 week before surgery and a sample of corpus cavernosal tissue was procured during surgery. The tissue was homogenized, measured for protein concentration, and used for western blot analysis. VEGF was selected as an AR marker and actin was used for protein normalization. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: VEGF and actin expression levels were analyzed using western blot analysis and ImageJ was used for quantification of antibody expression. RESULTS AND LIMITATIONS: AR signaling was measured in terms of VEGF expression. Above a T level of 200 ng/dl, there was no significant difference found in VEGF expression. Only one patient had a T level less than 200 ng/dl, limiting the generalizability of these results. In addition, all patients had a history of ED, and controls (patients without ED) were not included in the study. CONCLUSIONS: Above a serum T level of 200 ng/dl, there was no significant difference in AR signaling. This finding suggests that there could be a saturation level present in corpus cavernosal tissue that is approximately 200 ng/dl. PATIENT SUMMARY: Serum testosterone levels above a certain threshold may not be necessary for biological functions. Instead, it is most likely that there is an approximate serum testosterone level that fully saturates tissue androgen receptors and results in peak function in men.

In vitro efficacy of intralesional Collagenase Clostridium Histolyticum for the treatment of calcified Peyronie's disease plaques.

Peyronie's disease (PD) is defined by penile plaque formation and curvature causing sexual dysfunction. The only FDA-approved intralesional treatment is Collagenase Clostridium histolyticum (CCh). CCh contains two collagenases, AUX1 and AUXII, that break down the type I and type III collagen contained in plaques, leading to plaque dissolution and reduction in penile curvature. Peyronie's plaques, however, also contain fibrin and calcium, which CCh cannot digest. It is unclear if plaque calcification prevents CCh from breaking down plaques. We collected ten tissue samples: five calcified penile plaques and five control samples of corpus cavernosum. They were incubated in CCh or PBS. Soluble collagen measurements and collagen staining assays were completed to measure tissue breakdown. Calcified plaques incubated in CCh showed significantly higher levels of soluble collagen (301.07 ug ± 21.28 vs. PBS: 32.82 ug ± 3.68, p = 0.02), and significantly lower levels of collagen (type I and III) compared to tissues incubated in PBS (0.12 ± 0.08, vs. 0.44 ± 0.17, p = 0.002). When comparing different tissues (calcified vs. control) incubated in CCh and PBS solutions, there were no significant differences in collagen staining or breakdown. Although higher collagen staining was seen in the calcified group, soluble collagen showed no significant differences between control and calcified tissues in the CCh group (control: 0.08 ± 0.02 vs. calcified: 0.17 ± 0.09, p = 0.08) or the PBS group (control: 0.50 ± 0.23 vs. calcified: 0.39 ± 0.39, p = 0.23). CCh exposure led to significantly more tissue breakdown in both tissue groups when compared to PBS however, there was no significant difference in plaque digestion found between calcified and control tissue exposed to CCh or PBS. This suggests that plaque calcification does not affect the action of CCh. Further research into CCh for calcified plaques is necessary to inform clinicians as to the optimal management of this population.

Long vs Short Acting Testosterone Treatments: A Look at the Risks.

Prescriptions for testosterone therapy (TT) to treat testosterone deficiency have increased in recent years. The purpose of this review was to evaluate the risks of several treatment modalities to better counsel patients. Both short-acting and long-acting TT has been shown to restore normal serum testosterone levels and improve symptoms of testosterone deficiency. Short-acting pharmacology mimics normal physiology more closely than long-acting TT but requires multiple doses per day. Long-acting TT has a higher rate of patient adherence but is more likely to create supraphysiologic serum testosterone and pathologic sequelae.

Whole Exome Sequencing Identifies a Rare CFTR Mutation in Brothers With Anomalies of the Vas Deferens: A Case Study.

Congenital bilateral absence of the vas deferens (CBAVD) occurs in almost all men with cystic fibrosis. Prevailing theories on this pathophysiology relate to pathogenic mutations in the cystic fibrosis transmembrane regulator gene leading to agenesis or obliteration of vas deferens in utero. In this study, we present a case of two brothers with congenital anomalies of the vas deferens who were found to have carried a rare, heterozygous cystic fibrosis transmembrane regulator variant p.r347h without pulmonary or gastrointestinal signs or symptoms of cystic fibrosis .

Transcriptional Differences in Identical Twins With Different Reproductive Capacities: A Case Report.

Disorders of sperm production can be classified quantitatively as oligospermia (low sperm count) or azoospermia (no sperm during ejaculation). Numerous genes have been implicated in spermatogenesis. We describe a case of two identical twins who presented with different reproductive capabilities. One brother was infertile due to azoospermia, and the other, although oligospermic, previously naturally fathered a child. They were found to have differential gene expression based on RNA sequencing analysis. In the man with azoospermia, we found elevated E2F1 and HOXB9 gene expressions when compared with his brother, suggesting that the increased RNA expression of these genes could influence sperm production.

Next-generation sequencing analysis of semen microbiome taxonomy in men with nonobstructive azoospermia vs. fertile controls: a pilot study.

OBJECTIVES: To study how the semen microbiome profile in men with nonobstructive azoospermia (NOA) differs from that of fertile controls (FCs). DESIGN: Using quantitative polymerase chain reaction and 16S ribosomal RNA, we sequenced semen samples from men with NOA (follicle-stimulating hormone >10 IU/mL, testis volume <10 mL) and FCs and performed a comprehensive taxonomic microbiome analysis. SETTING: All patients were identified during evaluation at the outpatient male andrology clinic at the University of Miami. PATIENTS: In total, 33 adult men, including 14 diagnosed with NOA and 19 with proven paternity undergoing vasectomy, were enrolled. MAIN OUTCOME MEASURES: Bacterial species in the semen microbiome were identified. RESULTS: Alpha-diversity was similar between the groups, suggesting similar diversity within samples, whereas beta-diversity was different, suggesting differences in taxa between samples. In the NOA men, the phyla Proteobacteria and Firmicutes were underrepresented, and Actinobacteriota were overrepresented compared with FC men. At the genus level, Enterococcus was the most common amplicon sequence variant in both groups, whereas 5 genera differed significantly between the groups, including Escherichia and Shigella, Sneathia, and Raoutella. CONCLUSION: Our study showed significant differences in the seminal microbiome between men with NOA and fertile men. These results suggest a loss of functional symbiosis may be associated with NOA. Further research into the characterization and clinical utility of the semen microbiome and its causal role in male infertility is necessary.

Effect of Radiofrequency Electromagnetic Radiation Emitted by Modern Cellphones on Sperm Motility and Viability: An In Vitro Study.

BACKGROUND: Cellphones emit radiofrequency electromagnetic radiation (RF-EMR) for transmission of data for social media communication, web browsing, and music/podcast streaming. Use of Bluetooth ear buds has probably prolonged the time during which cellphones reside in the trouser pockets of men. It has been postulated that RF-EMR increases oxidative stress and induces free radical formation. OBJECTIVE: To investigate the effect of wireless-spectrum (4G, 5G, and WiFi) RF-EMR emitted by modern smartphones on sperm motility and viability and explore whether these effects can be mitigated using a physical barrier or distance. DESIGN, SETTING, AND PARTICIPANTS: Semen samples were obtained from fertile normozoospermic men aged 25-35 yr. A current-generation smartphone in talk mode was used as the RF-EMR source. A WhatsApp voice call was made using either 4G, 5G, or WiFi wireless connectivity. We determined if exposure effects were mitigated by either a cellphone case or greater distance from the semen sample. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The semen samples were analyzed according to 2010 World Health Organization laboratory guidelines. Statistical analysis was performed using SPSS v.28. RESULTS AND LIMITATIONS: We observed decreases in sperm motility and viability with WiFi exposure but not with exposure to 4G or 5G RF-EMR. With large variability among smartphones, continued research on exposure effects is needed. CONCLUSIONS: Our exploratory study revealed that sperm motility and viability are negatively impacted by smartphones that use the WiFi spectrum for data transmission. PATIENT SUMMARY: We looked at the effect of cellphone use on sperm motility and viability. We found that cellphones using WiFi connectivity for data usage have harmful effects on semen quality in men.