Urogenital infections in reproductive medicine

The negative impact of most relevant infections on fertility and assisted reproduction technology

Infections may act with variable impact on the physiopathology of the reproductive organs, determining infertility or reducing the outcomes of assisted reproduction technology. The aim of this narrative review is to describe the existing evidence regarding the pathogens with a supposed or recognized role in reproductive medicine. Viral hepatitis, as well as HIV, can reduce sperm quality. Syphilis carries a risk of erectile dysfunction and increased endometrial thickness. Chlamydia is the main cause of pelvic inflammatory disease. In relation to Mycoplasma and Ureaplasma spp., only few species seem to show a correlation with infertility and poor in-vitro fertilization outcomes. There is evidence of a role for bacterial vaginosis in early pregnancy loss. HPV infection in males seems to determine infertility. Herpesviruses are more a risk for fetuses than for fertility itself. Zika virus is responsible for altered early embryo development and waiting to conceive is recommended in suspected or confirmed cases. The impact of SARS-CoV-2 is yet to be elucidated. Rubella and toxoplasmosis can provoke important congenital defects and therefore screening is mandatory before conception; a vaccine for Rubella is recommended. Further and well-designed studies are still needed to better elucidate the role of some infectious agents, to improve fertility and its treatments.

Mesenchymal Stem-Cell Derived Exosome Therapy as a Potential Future Approach for Treatment of Male Infertility Caused by Chlamydia Infection

Some microbial sexually transmitted infections (STIs) have adverse effects on the reproductive tract, sperm function, and male fertility. Given that STIs are often asymptomatic and cause major complications such as urogenital inflammation, fibrosis, and scarring, optimal treatments should be performed to prevent the noxious effect of STIs on male fertility. Among STIs, Chlamydia trachomatis is the most common asymptomatic preventable bacterial STI. C. trachomatis can affect both sperm and the male reproductive tract. Recently, mesenchymal stem cells (MSCs) derived exosomes have been considered as a new therapeutic medicine due to their immunomodulatory, anti-inflammatory, anti-oxidant, and regenerative effects without consequences through the stem cell transplantation based therapies. Inflammation of the genital tract and sperm dysfunction are the consequences of the microbial infections, especially Chlamydia trachomatis. Exosome therapy as a noninvasive approach has shown promising results on the ability to regenerate the damaged sperm and treating asthenozoospermia. Recent experimental methods may be helpful in the novel treatments of male infertility. Thus, it is demonstrated that exosomes play an important role in preventing the consequences of infection, and thereby preventing inflammation, reducing cell damage, inhibiting fibrogenesis, and reducing scar formation. This review aimed to overview the studies about the potential therapeutic roles of MSCs-derived exosomes on sperm abnormalities and male infertility caused by STIs.

Air pollution from natural and anthropic sources and male fertility

Exposure to air pollution has been clearly associated with a range of adverse health effects, including reproductive toxicity. However, a limited amount of research has been conducted to examine the association between air pollution and male reproductive outcomes, specially semen quality. We performed a systematic review (up to March 2017) to assess the impact of environmental and occupational exposure to air pollution on semen quality. Epidemiological studies focusing on air pollution exposures and male reproduction were identified by a search of the PUBMED, MEDLINE, EBSCO and TOXNET literature bases. Twenty-two studies were included which assess the impact of air pollutants (PM_2.5, PM₁₀, SO₂, NOx, O₃, PAHs) on main semen parameters (sperm concentration, motility, morphology), CASA parameters, DNA fragmentation, sperm aneuploidy and the level of reproductive hormones. The number of studies found significant results supporting the evidence that air pollution may affect: DNA fragmentation, morphology and motility.In summary, most studies concluded that outdoor air pollution affects at least one of the assessed semen parameters. However the diversity of air pollutants and semen parameters presented in the studies included in the review and different study design caused lack of consistency in results and difficulties in comparison.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.

Association of asymptomatic Chlamydia trachomatis infection with male infertility and the effect of antibiotic therapy in improvement of semen quality in infected infertile men

The role of asymptomatic infections caused by Chlamydia trachomatis in male infertility and the efficacy of antibiotics in the treatment of this condition are not yet definitely determined. A total of 165 infertile males having abnormal semen parameters (study group) as well as 165 healthy fertile men (control group) were included. Semen samples were taken from all participants and after analysing for semen parameters, undergone real-time PCR, and reactive oxygen species (ROS) as well as total antioxidant capacity (TAC) assays. Infected individuals of study group were treated with antibiotic. One month after the treatment completion, second semen samples were taken and undergone all the tests mentioned. The frequency of C. trachomatis was significantly higher in the infertile men compared with the fertile ones (4.2% vs 0.6%). Most of the semen parameters were improved and reached their normal range, the level of TAC elevated and ROS level as well as ROS/TAC ratio reduced after antibiotic treatment. Moreover, wives of three infected infertile men (42.9%) became pregnant 4 months after the treatment completion. Our data suggest that asymptomatic infection caused by C. trachomatis is correlated with male infertility and antibiotic therapy can improve the semen quality and fairly treat the male infertility.

Ureaplasma spp. in male infertility and its relationship with semen quality and seminal plasma components

OBJECTIVE

We investigated the prevalence of Ureaplasma spp. in semen samples of infertile men in Shanghai, China and evaluated the correlation between the sperm parameters (seminal volume, sperm concentration, progressive motility and non-progressive) and the secretary function in these infectious populations.

METHODS

Semens were collected from 540 infertile men and 260 fertile control group in shanghai, China and subjected to standard bacterial and Ureaplasma spp. culture. Positive Ureaplasma spp. isolates were further tested by PCR to detect the biovars and serotypes of Ureaplasma spp. Sperm seminological variabilities were analyzed by Computer-Assisted Semen Analysis according to the fifth edition of World Health Organization (WHO) laboratory manual for the examination and processing of human semen. Seminal markers were measured by the automatic analyzer.

RESULTS

The prevalence of Ureaplasma spp. in semen specimens was 39.6% (214/540) and 19.2% (50/260) in infertile and control group, respectively. Significant difference was observed between the two groups (P < 0.001). Among all clinical isolates from infertile men (n = 214), 59.3% (n = 127) was Ureaplasma parvum (UPA), 26.2% (n = 56) was Ureaplasma urealyticum (UUR), and 14.5% (n = 31) was mixed species. While those numbers in control group (n = 50) were 64.0% (n = 32), 20.0% (n = 10), 16.0% (n = 8), respectively. There was no significant difference between any two groups (P > 0.05). The progressive motility and the NAG activity of infertile men infected with UPA and mixed species were significantly lower than those of UUR infected subgroup (P < 0.05).

CONCLUSIONS

The infection of Ureaplasma spp. plays an important pathogenic role in male infertility. UPA has higher pathogenicity on the progressive motility and the secretary function of epididymis than UUR.

Patients with cervical Ureaplasma Urealyticum and Chlamydia Trachomatis infection undergoing IVF/ICSI-ET: The need for new paradigm

Genital tract infections with ureaplasma urealyticum (UU) and chlamydia trachomatis (CT) are the most frequent sexually-transmitted disease worldwide. UU and CT infections are considered to be the leading cause for infertility and adverse pregnancy outcomes. However, little is known about the specific effect of cervical UU and CT infections on the etiology of female infertility, as well as the pregnancy outcomes of the patients undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET). In order to find the association between cervical UU and/or CT infection and pregnancy outcomes, we conducted a retrospective case-control study on the patients undergoing IVF/ICSI-ET with cervical UU and/or CT infection. A total of 2208 patients who received IVF/ICSI-ET were enrolled in this study. Data on the general conditions, pregnancy history and clinical pregnant outcomes were analyzed in terms of the cervical UU and CT detection. Our results revealed that cervical UU and CT infections were the risk factors for ectopic pregnancy and tubal factor-induced infertility. Moreover, the pregnancy rate, abortion rate, ectopic pregnancy rate and premature birth rate in patients with UU and/or CT infections showed no significant difference when compared with the control group. We recommend that cervical UU and CT detection should be an optional item for infertility patients and clinical UU detection should differentiate the subtypes of cervical UU. Positive cervical UU and CT infections should not be taken as strict contraindications for IVF/ICSI-ET.

Occupational, life stress and family functioning: does it affect semen quality?

BACKGROUND AND AIMS

Although psychological stress has been implicated as a cause of idiopathic infertility in both men and women, it has received little scientific attention among males as compared to females. The aim of the study was to examine the association between occupational, life stress, family functioning and semen quality.

METHODS AND RESULTS

The study population consisted of 327 men who were attending an infertility clinic for diagnostic purposes. Psychological stress was assessed based on two questionnaires: The Subjective Work Characteristics Questionnaire and the Perceived Stress Scale. The level of satisfaction with family functioning and support was evaluated by means of the APGAR Family Scale. The findings suggest that, on the one hand, exposure to occupational stressors can be negatively associated with semen quality (there was a positive association between stress and the percentage of sperm with DNA damage (p = 0.03) and atypical sperm (p = 0.05)); on the other hand, there was no correlation between the level of life stress and semen quality indicators. Negative associations were found between satisfaction with family functioning and the percentage of motile sperm cells (p = 0.02), VAP (p = 0.05), VSL (p = 0.05) and VCL (p = 0.04).

CONCLUSION

The study indicates that occupational stress can affect male semen quality; however, due to limited data on this issue, the obtained results should be confirmed in longitudinal studies.

Semen variation in a population of fertile donors: evaluation in a French centre over a 34-year period

Although it has been suspected that there is a decrease in semen quality over time, the results reported to date remain debatable because of methodological issues. The aim of the study reported here was to investigate the evolution of semen quality over time in a population of 1114 fertile candidates for sperm donation at CECOS, Tours, between 1976 and 2009. We investigated semen volume, sperm concentration, progressive motility, vitality, percentage of normal forms and multiple abnormalities index of the first ejaculate in this population. We did not find a decline in semen volume, whereas we observed a significant decrease in total sperm count (from 443.2 million in 1976 to 300.2 million in 2009), motility (from 64% in 1976 to 49% in 2009) and vitality (from 88% to 80%). Moreover, a significant decline in the percentage of normal forms was noted between 1976 and 1997 (from 67% to 26%) with a steady rise in the multiple abnormalities index between 1998 and 2009 (from 1.19 to 1.65). This study involving a population of fertile men from a restricted area revealed various degrees of decline in semen parameters over a period of 34 years. These findings will have to be compared with findings in other geographical areas.

Altered Toll-like receptor 2-mediated endotoxin tolerance is related to diminished interferon beta production

Induction of endotoxin tolerance leads to a reduced inflammatory response after repeated challenge by LPS and is important for resolution of inflammation and prevention of tissue damage. Enterobacterial LPS is recognized by the TLR4 signaling complex, whereas LPS of some non-enterobacterial organisms is capable of signaling independently of TLR4 utilizing TLR2-mediated signal transduction instead. In this study we report that Porphyromonas gingivalis LPS, a TLR2 agonist, fails to induce a fully endotoxin tolerant state in a human monocytic cell line (THP-1) and mouse bone marrow-derived macrophages. In contrast to significantly decreased production of human IL-8 and TNF-α and, in mice, keratinocyte-derived cytokine (KC), macrophage inflammatory protein-2 (MIP-2), and TNF-α after repeated challenge with Escherichia coli LPS, cells repeatedly exposed to P. gingivalis LPS responded by producing less TNF-α but sustained elevated secretion of IL-8, KC, and MIP-2. Furthermore, in endotoxin-tolerant cells, production of IL-8 is controlled at the signaling level and correlates well with NF-κB activation, whereas TNF-α expression is blocked at the gene transcription level. Interferon β plays an important role in attenuation of chemokine expression in endotoxin-tolerized cells as shown in interferon regulatory factor-3 knock-out mice. In addition, human gingival fibroblasts, commonly known not to display LPS tolerance, were found to be tolerant to repeated challenge by LPS if pretreated with interferon β. The data suggest that the inability of the LPS-TLR2 complex to induce full endotoxin tolerance in monocytes/macrophages is related to diminished production of interferon β and may partly explain the involvement of these LPS isoforms in the pathogenesis of chronic inflammatory diseases.

Male accessory gland infection and sperm parameters (review)

Male accessory gland infection (MAGI) has been identified among those diagnostic categories which have a negative impact on the reproductive function and fertility in males (Rowe et al., World Health Organization Manual for the Standardised Investigation and Diagnosis of the Infertile Couple, Cambridge University Press, Cambridge, 1993). MAGI is a hypernym which groups the following different clinical categories: prostatitis, prostate-vesiculitis and prostate-vesiculo-epididymitis. Some of the characteristics they share are: common diseases, mainly have a chronic course, rarely cause obstruction of the seminal pathways, can have an unpredictable intracanicular spread to one or more sexual accessory glands of the reproductive tract, as well as to one or both sides. In this review, we show that all components involving the inflammatory response (from the agents which first trigger it to each component of the inflammatory response dynamic) can deteriorate conventional and/or non-conventional sperm parameters arising from one or more of the following mechanisms: altered secretory function of the epididymis, seminal vesicles, and prostate which reduce the antioxidant properties or scavenging role of the seminal plasma; deterioration of spermatogenesis; and (unilateral or bilateral) organic or functional sub-obstruction of the seminal tract.