Evaluation and management of male genital tract infections in the setting of male infertility: an updated review

Current drawbacks and future perspectives in the diagnosis and treatment of male factor infertility, with a focus on FSH treatment: an expert opinion

PURPOSE

Infertility is defined as the inability to conceive after 1 year of unprotected intercourse, affecting approximately 15-20% of couples in Western countries. It is a shared problem within the couple; when the main issue lies with one of the partners, it is preferable to refer to "male factor" or "female factor" infertility rather than simply male or female infertility. Despite male factor infertility accounting for half of all couple infertility cases, the clinical approach to the male partner is not uniformly standardized across international guidelines.

METHODS

To provide an expert overview, we have comprehensively reviewed and critically analyzed the most up-to-date literature on this sensitive topic, leading to the development of a proposal for tailored assessment of the diagnostic-therapeutic pathway and preventive strategies. The diagnostic approach also considers that infertile men are objectively less healthy than their fertile counterparts of the same age and ethnicity.

RESULTS

This article discusses the diagnostic flow, the classification of male factor infertility, the definition of idiopathic infertility, the involvement of general health, and treatment recommendations, emphasizing follicle-stimulating hormone treatment in selected groups of patients.

CONCLUSION

We provide expert opinion on current drawbacks and future perspectives in this field, with practical advice for the clinical practice of general practitioners and expert in reproductive medicine.

Lycopene in male infertility

Male infertility is a major concern around the world, and efforts to find effective therapies to improve reproductive results are continuing. Factors such as genetics, hormonal disorders, lifestyle, and environmental pollutants have been mentioned as the pathoetiology of male infertility. The treatment of male infertility is far from optimal despite the recent signs of progress provided by assisted reproductive technology. Therefore, many efforts are being made to improve the therapeutical approaches to male infertility, which generally target the factors involved in the pathophysiology of the disease. Lycopene is a naturally occurring pigment belonging to the carotenoid family, which imparts a vibrant red color to various fruits and vegetables. It is widely assumed that lycopene may be an optimal option for the improvement of male fertility, however, the verification its therapeutic potential in male infertility has not been comprehensively reviewed. The study discusses the ability of lycopene to improve semen parameters, including sperm morphology, and motility which are important determinants of male reproductive health. Moreover, lycopene's capacity to regulate sex hormones, such as testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which play crucial roles in sperm production and maturation is explained. Additionally, lycopene effects on specific signaling pathways involved in male fertility, including prokineticin-2 (PROK2) and PI3K/Akt pathways, that influence sperm function are clarified. Furthermore, the impacts of lycopene as a potent antioxidant in defending against oxidative stress, a leading cause of male infertility, are presented. Overall, the results indicate that lycopene may have beneficial effects on improving male fertility by increasing sperm parameters, modulating sex hormones and signaling pathways, and providing antioxidant protection. Due to limited reports, additional clinical data is required to confirm the positive effects of lycopene on male fertility in humans.

Harnessing the power of miRNAs for precision diagnosis and treatment of male infertility

Infertility is a multifactorial reproductive system disorder, and most infertility cases occur in men. Semen testing is now thought to be the most important diagnostic test for infertile men; nonetheless, because of its limitations, the cause of infertility remains unknown for 40% of infertile men. Semen assessment's shortcomings indicate the need for improved and innovative diagnostic techniques and biomarkers worldwide. Non-coding RNAs with a length of roughly 18-22 nucleotides are called microRNAs (miRNAs). Most of our protein-coding genes are post-transcriptionally regulated by them. These molecules are unusual in bodily fluids, and aberrant variations in their expression can point to specific conditions like infertility. As a result, fresh potential biomarkers for the diagnosis and prognosis of various forms of male infertility may be represented by miRNAs. This review examined the most recent research revealing the association between different miRNAs' functions in male infertility and their expression patterns. Also, it aims to figure out the most recent strategies that could be applied for using such miRNAs as possible therapeutic targets for infertility treatment.

Protective Role of Physical Activity and Antioxidant Systems During Spermatogenesis

Oxidative stress is a significant factor that contributes to male infertility and sperm dysfunction. In this condition, an increase in ROS production exceeds the body's antioxidant defenses, resulting in a decline in spermatozoa quality and fertilizing capacity. Furthermore, excessive ROS production has been linked to the promotion of genomic damage, lipid peroxidation, inflammation, altered enzyme activity, and ultimately, irreversible alterations, cell death, and a decline in seminal parameters associated with male infertility. It is established that physical activity (PA), acting on inflammatory parameters and improving antioxidant defense, can alleviate the negative effects caused by free radicals, offering numerous health benefits and positively influencing sperm quality. The objective of this review is to highlight the mechanisms of ROS production, the physiological and pathophysiological roles of ROS in relation to the male reproductive system, and recent knowledge on the impact of some protocols of PA on these systems and the molecular mechanisms involved.

Associations of Ureaplasma urealyticum infection with male infertility and intrauterine insemination outcomes

ABSTRACT

Ureaplasma urealyticum (UU) is one of the most commonly occurring pathogens associated with genital tract infections in infertile males, but the impact of seminal UU infection in semen on intrauterine insemination (IUI) outcomes is poorly understood. We collected data from 245 infertile couples who underwent IUI at The First Affiliated Hospital of USTC (Hefei, China) between January 2021 and January 2023. The subjects were classified into two groups according to their UU infection status: the UU-positive group and the UU-negative group. We compared semen parameters, pregnancy outcomes, and neonatal birth outcomes to investigate the impact of UU infection on IUI outcomes. There were no significantly statistical differences in various semen parameters, including semen volume, sperm concentration, total and progressive motility, sperm morphology, leukocyte count, the presence of anti-sperm antibody, and sperm DNA fragmentation index (DFI), between the UU-positive and UU-negative groups of male infertile patients (all P > 0.05). However, the high DNA stainability (HDS) status of sperm differed between the UU-positive and UU-negative groups, suggesting that seminal UU infection may affect sperm nuclear maturation ( P = 0.04). Additionally, there were no significant differences in pregnancy or neonatal birth outcomes between the two groups (all P > 0.05). These results suggest that IUI remains a viable and cost-effective option for infertile couples with UU infection who are facing infertility issues.

Impact of Human Papillomavirus (HPV) on Male and Female Fertility

Human papillomaviruses (HPVs) are responsible for the majority of sexually transmitted infections (STIs), some of which are oncogenic and can cause oropharyngeal or genital cancers. The HPV prevalence at the genital level varies according to the population studied but is higher in the seminal fluid of men suffering from idiopathic infertility than in the general population. The involvement of HPV in male infertility is supported by several studies suggesting that this virus can affect sperm quality by altering sperm DNA integrity, motility, number, viability, and morphology, and by inducing the production of anti-sperm antibodies (ASAs). HPVs may also have an impact on female fertility, mainly by increasing the risk of miscarriage and premature delivery and by altering the implantation of endometrial trophoblastic cells. In addition, an association with vaginal bacterial dysbiosis, notably involving Gardnerella vaginalis, or co-infection with an STI agent, serves as an aggravating factor. The aim of this review is to present current data on the potential role of HPVs in male and female infertility, along with data on infertility prevention and treatment strategies and the impact of vaccination in this context.

Impact of Ureaplasma urealyticum infection on semen parameters and in vitro fertilization outcomes in infertile men

Introduction

Ureaplasma urealyticum (UU) is a common pathogen associated with genital tract infections in infertile males. However, its impact on semen quality, embryo development, and in vitro fertilization (IVF) outcomes remains underexplored. This study aims to evaluate the effect of male UU infection on semen parameters, embryo development, pregnancy outcomes, and neonatal health in infertile couples.

Methods

A retrospective analysis was conducted on 1,215 infertile couples at the First Hospital of USTC. Participants were divided into two groups based on the male partner's UU infection status: UU-positive (n=249) and UU-negative (n=966). Semen parameters (sperm concentration, motility, morphology, anti-sperm antibodies, DNA stainability) were assessed. Embryo development was evaluated through fertilization rates and blastocyst formation rates. Pregnancy outcomes (clinical pregnancy, live birth rates, miscarriage rate) and neonatal health (gestational age, birth weight, Apgar scores, preterm delivery) were also compared.

Results

Semen parameters, including sperm concentration, motility, and morphology, were similar between the UU-positive and UU-negative groups. However, the UU-positive group had significantly higher levels of anti-sperm antibodies (ASA) (p=0.020) and higher DNA stainability (HDS) (p=0.014). Despite these differences, embryo quality, as measured by fertilization rates and blastocyst formation rates, was not significantly different between the two groups. Pregnancy outcomes, including clinical pregnancy and live birth rates, were also comparable. While the UU-positive group had a slightly higher miscarriage rate, this difference was not statistically significant. Neonatal outcomes, including gestational age, birth weight, Apgar scores, and preterm delivery rate, did not differ significantly between the two groups.

Discussion

The study suggests that while male UU infection may adversely affect certain semen parameters, its impact on IVF outcomes-such as embryo quality, pregnancy rates, and neonatal health-appears to be minimal. These findings support the continued use of IVF as a viable and safe option for infertile couples with male UU infection, as it does not significantly influence reproductive or neonatal outcomes.

Pharmacological therapies for male infertility

Male factor infertility is a multifaceted problem that affects approximately 50% of couples suffering from infertility. Causes of male infertility include endocrine disturbances, gonadotoxins, genetic abnormalities, varicocele, malignancies, infections, congenital or acquired urogenital abnormalities, iatrogenic factors, immunological factors, and idiopathic reasons. There are a variety of treatment options for male infertility, depending on the underlying cause(s). These can include surgical treatments, medical/hormonal therapies, and assisted reproductive techniques (ART), which can be combined with surgical sperm retrieval (SSR) if necessary. In this review article, the pharmacological therapies for male infertility are grouped by their underlying causes. Some of these therapies are targeted and specific, while others are used empirically to treat idiopathic male infertility. This will include treatments to optimize infertility in patients who have hypogonadism, ejaculatory dysfunction, infections, or idiopathic male infertility. Finally, we will provide an overview of the future directions of pharmacological therapies for male infertility. Significance Statement Male infertility is a significant worldwide problem. Detailed knowledge of the pharmacological therapies available will ensure the prescription of appropriate therapy and avoid the use of unnecessary or harmful treatments.

Role of Leukocytospermia in the Management of Male Infertility: Decoding a Mystery for the Busy Clinicians

Leukocytospermia, defined as a leukocyte concentration in semen exceeding 1×106 leukocytes/mL, significantly impacts male reproductive health by affecting sperm functionality and fertility outcomes. This condition arises from various etiological factors, including infections, autoimmune responses, lifestyle factors, and other physiological conditions. Adverse effects on sperm associated with leukocytospermia include acrosome damage and abnormalities in the sperm midpiece and tail. The review explores the complex interplay between leukocytospermia and oxidative stress, emphasizing the harmful effects on sperm DNA integrity and overall sperm quality. Due to the multifactorial nature of leukocytospermia, diagnosing this condition presents several challenges. Effective management strategies discussed include the use of antibiotics, anti-inflammatory agents, and assisted reproductive technologies. Diagnostic methods range from traditional peroxidase staining to more advanced techniques such as immunocytochemistry and flow cytometry, which offer higher sensitivity and specificity. Infections of the male genital tract, particularly male accessory gland infection and male genital tract infection, play a significant role in the etiology of leukocytospermia. These infections lead to an inflammatory response, resulting in leukocyte infiltration into the semen. Systemic conditions like diabetes mellitus and autoimmune disorders also contribute to leukocytospermia by provoking inflammatory responses that facilitate leukocyte presence in semen. This review underscores the importance of a comprehensive diagnostic approach that includes patient history, physical examination, and advanced laboratory tests. Treatment is tailored to the identified underlying cause, whether infectious or non-infectious. Lifestyle modifications, such as reducing stress, improving diet, and avoiding environmental toxins, are also recommended to enhance semen quality. For clinicians, this review provides a concise yet thorough overview of leukocytospermia, integrating the latest research findings and clinical insights to aid in the effective management of this condition, ultimately aiming to improve patient care in male reproductive health.

Impact of high-risk and low-risk human papillomavirus infections on the male genital tract: effects on semen inflammation and sperm quality

Human Papillomavirus (HPV), a prevalent sexually transmitted infection, comprises high-risk (HR-HPV) and low-risk (LR-HPV) viruses, the former posing a high risk for developing malignancies whereas the latter mainly for benign warts. Despite increasing awareness of HPV's impact on men's health, the influence of HR-HPV and LR-HPV urogenital infections on male fertility potential remains uncertain. This study aimed to investigate whether male urogenital infection with HR- or LR-HPV associates with impaired sperm quality, oxidative stress, and inflammation. A total of 205 male patients attending an urology clinic were enrolled. Semen samples were analyzed for HPV using PCR and genotyped by RFLP. Semen quality was evaluated following WHO guidelines. Semen leukocytes, reactive oxygen species (ROS), and sperm viability were analyzed using flow cytometry. HPV was detected in 19% (39/205) of semen samples. HR-HPV infections were more prevalent, with HPV-16 being the most frequent genotype. Neither HR-HPV nor LR-HPV were associated with significant alterations in routine sperm quality parameters. However, HR-HPV+ individuals showed significantly higher levels of sperm necrosis and exhibited increased proportions of ROS+ spermatozoa compared to LR-HPV+ or control individuals. Furthermore, no significant semen inflammation was detected in patients infected with either HR-HPV or LR-HPV, and unexpectedly reduced semen leukocytes and inflammatory cytokines (IL-6 and IL-1β) were observed in HR-HPV+ patients compared to controls. These observations underscore the importance of comprehensive HPV screening, including genotyping, in urology and fertility clinics to understand the progression of the infection, potential adverse effects on reproductive health, and the oncogenic risks involved.

Leukocytospermia and/or Bacteriospermia: Impact on Male Infertility

Infertility is a globally underestimated public health concern affecting almost 190 million people, i.e., about 17.5% of people during their lifetime, while the prevalence of male factor infertility is about 7%. Among numerous other causes, the prevalence of male genital tract infections reportedly ranges between 10% and 35%. Leukocytospermia is found in 30% of infertile men and up to 20% in fertile men. Bacterial infections cause an inflammatory response attracting leukocytes, which produce reactive oxygen species (ROS) and release cytokines, both of which can cause damage to sperm, rendering them dysfunctional. Although leukocytospermia and bacteriospermia are both clinical conditions that can negatively affect male fertility, there is still debate about their impact on assisted reproduction outcomes and management. According to World Health Organization (WHO) guidelines, leukocytes should be determined by means of the Endtz test or with monoclonal antibodies against CD15, CD68 or CD22. The cut-off value proposed by the WHO is 1 × 106 peroxidase-positive cells/mL. For bacteria, Gram staining and semen culture are regarded as the "gold standard", while modern techniques such as PCR and next-generation sequencing (NGS) are allowing clinicians to detect a wider range of pathogens. Whereas the WHO manual does not specify a specific value as a cut-off for bacterial contamination, several studies consider semen samples with more than 103 colony-forming units (cfu)/mL as bacteriospermic. The pathogenic mechanisms leading to sperm dysfunction include direct interaction of bacteria with the male germ cells, bacterial release of spermatotoxic substances, induction of pro-inflammatory cytokines and ROS, all of which lead to oxidative stress. Clinically, bacterial infections, including "silent" infections, are treatable, with antibiotics being the treatment of choice. Yet, non-steroidal antiphlogistics or antioxidants should also be considered to alleviate inflammatory lesions and improve semen quality. In an assisted reproduction set up, sperm separation techniques significantly reduce the bacterial load in the semen. Nonetheless, contamination of the semen sample with skin commensals should be prevented by applying relevant hygiene techniques. In patients where leukocytospermia is detected, the causes (e.g. infection, inflammation, varicocele, smoking, etc.) of the leukocyte infiltration have to be identified and addressed with antibiotics, anti-inflammatories or antioxidants in cases where high oxidative stress levels are detected. However, no specific strategy is available for the management of leukocytospermia. Therefore, the relationship between bacteriospermia and leukocytospermia as well as their specific impact on functional sperm parameters and reproductive outcome variables such as fertilization or clinical pregnancy must be further investigated. The aim of this narrative review is to provide an update on the current knowledge on leukocytospermia and bacteriospermia and their impact on male fertility.

Unraveling the Impact of Sperm DNA Fragmentation on Reproductive Outcomes

In recent years, there has been a growing interest in identifying subcellular causes of male infertility, and sperm DNA fragmentation (SDF) research has been at the forefront of this focus. DNA damage can occur during spermatogenesis due to faulty chromatin compaction or excessive abortive apoptosis. It can also happen as sperm transit through the genital tract, often induced by oxidative stress. There are several methods for SDF testing, with the sperm chromatin structure assay, terminal deoxynucleotidyl transferase d-UTI nick end labeling (TUNEL) assay, comet assay, and sperm chromatin dispersion test being the most commonly used. Numerous studies strongly support the negative impact of SDF on male fertility potential. DNA damage has been linked to various morphological and functional sperm abnormalities, ultimately affecting natural conception and assisted reproductive technology outcomes. This evidence-based review aims to explore how SDF influences male reproduction and provide insights into available therapeutic options to minimize its detrimental impact.