The impact of COVID-19 vaccine on sperm quality

Evaluating male sexual function and reproductive health during Omicron outbreak in China

There are currently no studies exploring omicron infection and male sexual function and semen quality. Our aim was to estimate changes in sexual function and semen quality in men recovering from infection since the COVID-19 Omicron pandemic started in China in late 2022. We collected 1540 questionnaires and assessed male function before infection and acute phase after infection by using International Index of Erectile Function-5, Premature Ejaculation Diagnostic Tool, and Arizona Sexual Experience Scale. We also collected the before and after semen analysis results of 247 male patients. During the acute phase after infection, the proportion of erectile dysfunction was significantly higher than before infection, but ejaculatory function was not significantly altered; In addition, semen analysis showed significant difference in semen concentration, semen activity and PR a+b sperm forward movement after infection compared to pre-infection.: COVID-19 Omicron can affect erectile function as well as sexual experience in male patients in the acute phase. Decreased sexual function due to COVID-19 Omicron may be related to body temperature and anxiety during infection.

SARS-CoV-2-Vaccine-Related Endocrine Disorders: An Updated Narrative Review

The emergence of the COVID-19 pandemic has led to the rapid and worldwide development and investigation of multiple vaccines. While most side effects of these vaccines are mild and transient, potentially severe adverse events may occur and involve the endocrine system. This narrative review aimed to explore the current knowledge on potential adverse endocrine effects following COVID-19 vaccination, with thyroid disorders being the most common. Data about pituitary, adrenal, diabetes, and gonadal events are also reviewed. This review also provides a comprehensive understanding of the pathogenesis of endocrine disorders associated with SARS-CoV-2 vaccines. PubMed/MEDLINE, Embase database (Elsevier), and Google Scholar searches were performed. Case reports, case series, original studies, and reviews written in English and published online up to 31 August 2023 were selected and reviewed. Data on endocrine adverse events of SARS-CoV-2 vaccines are accumulating. However, their causal relationship with COVID-19 vaccines is not strong enough to make a definite conclusion, and further studies are needed to clarify the pathogenesis mechanisms of the endocrine disorders linked to COVID-19 vaccines.

Impact of COVID-19 on sperm quality and the prostaglandin and polyamine systems in the seminal fluid

BACKGROUND

The implications of SARS-CoV-2 infection on male fertility remain largely unknown. Besides their well-known pro- and anti-inflammatory actions, prostaglandins and polyamines are present in semen, where they play key roles in sperm quality.

OBJECTIVES

To analyze semen parameters, oxidative profile and the seminal fluid prostaglandin and polyamine systems in samples collected from individuals without coronavirus disease 2019 diagnosis and men who recovered from coronavirus disease 2019.

MATERIALS AND METHODS

This study compared semen collected from men without positive coronavirus disease 2019 diagnosis with samples obtained from individuals 1-6 months and 7-30 months post SARS-CoV-2 infection. Semen parameters, thiobarbituric acid reactive substances, cyclooxygenase 2 expression by fluorescence immunocytochemistry and immunoblotting, prostaglandin levels by enzyme immunoassay, ornithine decarboxylase activity by a radioactive assay, and polyamine and acetylated polyamine levels by thin-layer chromatography were assessed.

RESULTS

In both groups of semen samples from coronavirus disease 2019 recovered men, sperm vitality, total and progressive sperm motility, and putrescine levels were significantly decreased when compared with samples from the uninfected group. In contrast, lipid peroxidation, leukocyte-associated cyclooxygenase 2 expression, and prostaglandin D2 levels were higher in semen from coronavirus disease 2019 recovered men than in samples from uninfected individuals. While sperm concentration and morphology, ornithine decarboxylase activity, and N-acetylputrescine levels were statistically diminished in semen obtained up to 6 months after coronavirus disease 2019 recovery, these parameters remained unchanged when samples were collected 7-30 months after coronavirus disease 2019 recovery. Coronavirus disease 2019 vaccination did not show negative effects on any of the parameters evaluated.

DISCUSSION AND CONCLUSION

Our work provides insights into the detrimental impact of coronavirus disease 2019 on several sperm parameters, in some cases, even more than a year after SARS-CoV-2 infection, which would be accompanied by alterations in the seminal fluid prostaglandin and polyamine profiles. Therefore, future treatments targeting the prostaglandin and polyamine pathways in coronavirus disease 2019 recovered men could lead to a successful reinstatement of semen parameters.

The type of COVID-19 vaccination does not affect reproductive function and pregnancy outcomes in infertile couples

Introduction

Studies on the effect of vaccine type and two other vaccines other than inactivated vaccines approved in China on in vitro fertilization (IVF) pregnancy outcomes are rare. To complement and confirm the existing findings, this research aimed to investigate whether there are adverse effects of different vaccine types in females and males on reproductive function and clinical pregnancy.

Methods

This retrospective study enrolled 6,455 fresh embryo transfer cycles at the First Affiliated Hospital of Zhengzhou University between May 1, 2021, and October 31, 2022. The primary outcome is the clinical pregnancy rate (CPR). At the same time, the secondary results are the number of oocytes retrieved, two pronuclei (2PN) rate, blastocyst formation rate, high-quality blastocyst rate, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DNA fragment index (DFI) rate).

Results

In the comparison of ovarian stimulation indicators, no statistically significant differences (P > 0.05) were found in Gn days, endometrial thickness, 2PN rate, metaphase 2 (MII) rate, high-quality embryo rate, and blastocyst formation rate. No significant differences (P>0.05) were found in age, body mass index (BMI), education level, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DFI rate) in these four groups. The multivariate regression model showed that neither the types of vaccines nor the vaccination status of both infertile couples significantly affected clinical pregnancy.

Discussion

The type of vaccine does not appear to have an unfavorable effect on ovarian stimulation, embryo development, semen parameters, and clinical pregnancy.

Updates in the pathophysiology of COVID-19 infection in male reproductive and sexual health: a literature review

This extensive comprehensive review explores the impact of the Coronavirus disease 2019 (COVID-19) pandemic on men's sexual and reproductive health. We conducted a literature review focusing on the possible pathophysiology by which severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) affects men's sexual and reproductive systems. We reviewed most of the studies that reported the impact of SARS-CoV-2 infection on the Testicular, Epididymal, Prostatic, and Penile tissue. Also, we focused on evaluating the SARS-CoV-2 infection on semen parameters and male reproductive hormones. Finally, we reviewed the COVID-19 vaccine's effect on male reproductive and sexual health. Findings revealed the adverse consequences of SARS-CoV-2 at cellular and organ levels on the male genital tract. However, the reported data are still controversial. The initial data regarding COVID-19 vaccination was promising promoted safety for men's reproductive and sexual health. We conclude this paper by offering recommendations to address these adverse consequences and potentially improve sexual and reproductive health among men in the post-COVID-19 pandemic era.

Effects of SARS-CoV-2 Vaccines on Sperm Quality: Systematic Review

BACKGROUND

The COVID-19 pandemic, caused by SARS-CoV-2, has triggered a global public health crisis of unprecedented proportions. SARS-CoV-2 vaccination is a highly effective strategy for preventing infections and severe COVID-19 outcomes. Although several studies have concluded that COVID-19 vaccines are unlikely to affect fertility, concerns have arisen regarding adverse events, including the potential impact on fertility; these concerns are plagued by limited and inconsistent evidence.

OBJECTIVE

This review aims to provide a recent assessment of the literature on the impact of COVID-19 vaccines on male sperm quality. The possible impact of COVID-19 vaccines on fertility potential was also examined to draw a clearer picture and to evaluate the effects of COVID-19 on male reproductive health.

METHODS

PubMed, Scopus, Web of Science, Embase, and Cochrane databases were searched from their inception to October 2023. Eligible studies included articles reporting SARS-CoV-2 vaccination and human semen quality and fertility, as well as the impact of vaccination on assisted reproductive technology treatment outcomes. The quality of cohort studies was assessed using the Newcastle-Ottawa Scale, and the quality of cross-sectional studies was assessed using the quality evaluation criteria recommended by the Agency for Healthcare Research and Quality. The systematic review followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

RESULTS

The initial literature search yielded 4691 records by searching 5 peer-reviewed databases (PubMed, Scopus, Web of Science, Embase, and Cochrane). Finally, 24 relevant studies were selected for our study. There were evident research inequalities at the regional level, with the United States and Western European countries contributing 38% (9/24) of the studies, Middle Eastern countries contributing 38% (9/24), China accounting for 21% (5/24), and Africa and South America accounting for none. Nonetheless, the overall quality of the included studies was generally good. Our results demonstrated that serious side effects of the COVID-19 vaccine are extremely rare, and men experience few problems with sperm parameters or reproductive potential after vaccination.

CONCLUSIONS

On the basis of the studies published so far, the COVID-19 vaccine is safe for male reproductive health. Obviously, vaccination is a wise option rather than experience serious adverse symptoms of viral infections. These instances of evidence may help reduce vaccine hesitancy and increase vaccination coverage, particularly among reproductive-age couples. As new controlled trials and prospective cohort studies with larger sample sizes emerge, the possibility of a negative effect of the COVID-19 vaccine on sperm quality must be further clarified.

Effects of COVID-19 vaccination on human fertility: a post-pandemic literature review

Although vaccination with the Coronavirus disease 2019 vaccine is important and effective in the prevention of SARS-CoV-2 infection, the public expressed concerns regarding the adverse effects of vaccine on fertility. Some reviews have focused on it, they have been unable to collect sufficient research data because of the earlier publication period. As relevant evidence has gradually increased, we reviewed these studies from the perspectives of males, females with or without pregnancy, and different vaccine types. The results suggest that although males may experience fluctuations in semen parameters within their physiological ranges after receiving the vaccine, it has not yet reached a level of influence on the partner's pregnancy probability. As to female without pregnancy, it is believed that vaccination will not affect fertility; however, more research is needed to explore the short-term impact. Vaccination during any trimester is considered safe in pregnant women.

Effects of COVID-19 or vaccines for SARS-COV-2 on sperm parameters: A systematic review and meta-analysis

This systematic review and meta-analysis assessed the effects of SARS-Cov-2 and mRNA vaccines on male reproduction. We conducted a comprehensive search using terms such as "COVID-19," "vaccine," and "sperm parameters" on various electronic databases, including MEDLINE (PubMed), BVS (LILACS and others), Embase (Elsevier), and Cochrane Library. We included observational studies, including cohort, case-control, and cross-sectional studies. Of the 2054 records initially identified, we carefully examined 47 full-text articles and excluded 26 articles for specific reasons, ultimately including 21 studies for our analysis. Among these, 16 studies focused on assessing seminal parameters in patients with COVID-19, while five studies investigated the effects of COVID vaccines on seminal parameters. A meta-analysis of seminal parameters in men before and after the COVID-19 pandemic revealed significant differences in seminal concentration, progressive motility, total motility, and normal morphology. These findings indicate a positive impact of the analyzed parameters before the onset of COVID-19. However, the quality of the evidence was considered low. In contrast, a meta-analysis of five studies evaluating seminal parameters before and after the SARS-Cov-2 vaccine did not show any significant differences in total motility. This analysis, involving 256 men from four studies, provided low-quality evidence, suggesting that mRNA vaccines do not affect male reproduction. Overall, our findings suggest that seminal parameters exhibit considerable variability depending on specific outcomes and the study design. However, based on available evidence, it appears that mRNA vaccines do not have detrimental effects on male reproductive function.

Effects of the Severe Acute Respiratory Syndrome Coronavirus 2 Inactivated Vaccine on the Outcome of Frozen Embryo Transfers: A Large Scale Clinical Study

Background

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a life-threatening infectious disease that has become a global pandemic.

Objective

This study aimed to explore the effects of SARS-CoV-2 inactivated vaccine on the outcome of frozen embryo transfer (FET).

Methods

We grouped patients who underwent FET between August 2021 and March 2022 based on their vaccination status, number of doses, and the interval between the last dose and the FET, and then compared the differences in pregnancy outcomes among the groups.

Results

There were 1084 vaccinated patients and 1228 non-vaccinated ones. There were significant differences in the live birth rate between the vaccination and non-vaccination groups (16.61% vs 28.26%), among the one-dose, two-dose, and three-dose groups (22.28% vs 19.51% vs 7.27%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (38.38% vs 27.27% vs 12.03%). There were significant differences in the persistent pregnancy rate between the vaccination and non-vaccination groups (22.88% vs 14.09%), among the one-dose, two-dose, and three-dose groups (14.51% vs 23.80% vs 38.18%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (1.01% vs 8.44% vs 28.16%). There were significant differences in the neonatal weight between the vaccination and non-vaccination groups [3805.50 (3746.00-3863.50) vs 2970.00 (2500.00-3400.00)]. There were significant differences in the premature birth rate among the one-dose, two-dose, and three-dose groups (23.26% vs 34.59% vs 100.00%), and among the groups with interval ≤ 1 month, 1-2 months, and ≥ 2 months (15.79% vs 21.43% vs 37.00%).

Conclusion

Pregnancy outcomes were not affected by taking the SARS-CoV-2 inactivated vaccine before FET, the number of doses, and the interval between doses. These findings provide evidence supporting the safety of administering the SARS-CoV-2 inactivated vaccine during pregnancy, which can be used as a guide for vaccinating patients undergoing ART.

COVID-19 and Male Infertility: Is There a Role for Antioxidants?

Coronavirus disease 19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), jeopardizes male fertility because of the vulnerability of the male reproductive system, especially the testes. This study evaluates the effects of the virus on testicular function and examines the potential role of antioxidants in mitigating the damage caused by oxidative stress (OS). A comprehensive PubMed search examined exocrine and endocrine testicular function alteration, the interplay between OS and COVID-19-induced defects, and the potential benefit of antioxidants. Although the virus is rarely directly detectable in sperm and testicular tissue, semen quality and hormonal balance are affected in patients, with some changes persisting throughout a spermatogenesis cycle. Testicular pathology in deceased patients shows defects in spermatogenesis, vascular changes, and inflammation. Acute primary hypogonadism is observed mainly in severely infected cases. Elevated OS and sperm DNA fragmentation markers suggest redox imbalance as a possible mechanism behind the fertility changes. COVID-19 vaccines appear to be safe for male fertility, but the efficacy of antioxidants to improve sperm quality after infection remains unproven due to limited research. Given the limited and inconclusive evidence, careful evaluation of men recovering from COVID-19 seeking fertility improvement is strongly recommended.

SARS-CoV-2, fertility and assisted reproduction

BACKGROUND

In 2020, SARS-CoV-2 and the COVID-19 pandemic had a huge impact on the access to and provision of ART treatments. Gradually, knowledge of the virus and its transmission has become available, allowing ART activities to resume. Still, questions on the impact of the virus on human gametes and fertility remain.

OBJECTIVE AND RATIONALE

This article summarizes published data, aiming to clarify the impact of SARS-CoV-2 and the COVID-19 disease on human fertility and assisted reproduction, as well as the impact of vaccination, and from this, provide answers to questions that are relevant for people contemplating pregnancy and for health care professionals.

SEARCH METHODS

PUBMED/MEDLINE and the WHO COVID-19 database were searched from inception to 5 October 2022 with search terms focusing on 'SARS-CoV-2' and gametes, embryos, reproductive function, fertility and ART. Non-English studies and papers published prior to 2020 were excluded, as well as reviews and non-peer reviewed publications. Full papers were assessed for relevance and quality, where feasible.

OUTCOMES

From the 148 papers included, the following observations were made. The SARS-CoV-2-binding proteins, angiotensin-converting enzyme 2 (ACE2) and type II transmembrane serine protease (TMPRSS2), are expressed in the testis, but co-expression remains to be proven. There is some evidence of SARS-CoV-2 RNA in the ejaculate of COVID-19 patients with severe disease, but not in those with mild/moderate disease. SARS-CoV-2 infection can impair spermatogenesis, but this seems to resolve after one spermatogenic cycle. Testosterone levels seem to be lower during and after COVID-19, but long-term data are lacking; disease severity may be associated with testosterone levels. COVID-19 cannot be considered a sexually transmitted disease. There is no co-expression of ACE2 and TMPRSS2 in the myometrium, uterus, ovaries or fallopian tubes. Oocytes seem to have the receptors and protease machinery to be susceptible to SARS-CoV-2 infection; however, viral RNA in oocytes has not been detected so far. Women contemplating pregnancy following COVID-19 may benefit from screening for thyroid dysfunction. There is a possible (transient) impact of COVID-19 on menstrual patterns. Embryos, and particularly late blastocysts, seem to have the machinery to be susceptible to SARS-CoV-2 infection. Most studies have not reported a significant impact of COVID-19 on ovarian reserve, ovarian function or follicular fluid parameters. Previous asymptomatic or mild SARS-CoV-2 infection in females does not seem to negatively affect laboratory and clinical outcomes of ART. There are no data on the minimum required interval, if any, between COVID-19 recovery and ART. There is no evidence of a negative effect of SARS-CoV-2 vaccination on semen parameters or spermatogenesis, ovarian function, ovarian reserve or folliculogenesis. A transient effect on the menstrual cycle has been documented. Despite concerns, cross reactivity between anti-SARS-CoV-2 spike protein antibodies and Syncytin-1, an essential protein in human implantation, is absent. There is no influence of mRNA SARS-CoV-2 vaccine on patients' performance during their immediate subsequent ART cycle. Pregnancy rates post-vaccination are similar to those in unvaccinated patients.

WIDER IMPLICATIONS

This review highlights existing knowledge on the impact of SARS-CoV-2 infection or COVID-19 on fertility and assisted reproduction, but also identifies gaps and offers suggestions for future research. The knowledge presented should help to provide evidence-based advice for practitioners and couples contemplating pregnancy alike, facilitating informed decision-making in an environment of significant emotional turmoil.

Sperm DNA fragmentation in men vaccinated with Gam-COVID-Vac (Sputnik V)

Aim. To perform comparative analysis of sperm characteristics and DNA fragmentation in men vaccinated with GamCOVID-Vac (Sputnik V) and unvaccinated men.

Materials and methods. Characteristics ofsemen analysis and DNA fragmentation index in ejaculate samples of 122 men, 28 of whom were vaccinated with Gam-COVID-Vac (Sputnik V), were analyzed. Study participants did not have history of coronavirus infection COVID-19. Vaccinated patients were divided into 2 groups: group 1 (n = 10) included patients for whom the time between full vaccination (2 doses of the vaccine) and ejaculate sampling was shorter than 75 days; and the group 2 (n = 18) included patients for whom the time between vaccination and ejaculate sampling was longer than 75 days. Unvaccinated men comprised the control group (group 3, n = 94). Standard semen analysis was performed in accordance with the accepted laboratory guidelines of the World Health Organization (2010). DNA fragmentation was evaluated using fluorescent labelling of single- and double-strand DNA breaks (TUNEL).

Results. Totalsperm countin the group 1 was 265 ± 75 million, in the group 2 – 355 ± 67 million, in the group 3 – 304 ± 26 million. Progressive motile (PR)sperm in the group 1was 18.5 ± 1.9 %, in the group 2 – 23.2 ± 3.0 %, in the group 3 – 18.2 ± 1.1 %. Normal sperm morphology in the group 1 was 4.0 ± 0.5 %, in the group 2 – 5.8 ± 0.9 %, in the group 3 – 4.1 ± 0.3 %. The best ejaculate quality was observed in patients of the group 2, however, no statistically significant differences in semen analysis characteristics between the groups were found. Percentage of sperm with fragmented DNA (DNA fragmentation index, DFI) in the group 1 varied between 4.6 and 31.4 %, in the group 2 between 0.8 and 36.5 %, in the group 3 (control) between 1.3 and 39.8 %. Mean number of germ cells with DNA breaksin the group 1 (12.5 ± 2.4 %) was higher than in the group 2 (10.9 ± 2.0 %) and control group (10.5 ± 0.7 %), but with no statistical significance. Percentage of patients with DNA fragmentation index above the reference value (≤15 %) in the groups 1, 2 and 3 was 20, 22 and 18 % respectively. In 3 of 6 patients with increased DFI in the groups 1 and 2, this value was above the reference level even before vaccination.

Conclusion. No significant effect of vaccination with Sputnik V on sperm DNA fragmentation level in men was observed.

Effect of COVID-19 vaccination on semen parameters: A systematic review and meta-analysis

The aim of this study was to investigate the effect of coronavirus disease 2019 (COVID-19) vaccination on semen parameters through systematic review and meta-analysis. PubMed, EMBASE, Web of Science, and Cochrane Library were comprehensively searched by June 2022. Studies were considered eligible if they compared semen parameters before and after COVID-19 vaccination or between vaccinated and unvaccinated men, with no restrictions on vaccine types or doses. The effect size was calculated as mean difference (MD) with 95% confidence interval (CI) using a random-effects model. Subgroup and sensitivity analyses were conducted to assess the sources of heterogeneity measured by the I² statistic, with publication bias evaluated by Egger's test. Twelve cohort studies involving 914 participants fulfilled the inclusion criteria. In a comparison of vaccinated versus unvaccinated group, the pooled data revealed no significant differences in semen volume (MD = 0.18 ml, 95% CI -0.02 to 0.38), sperm concentration (MD = 1.16 million/ml, 95% CI -1.34 to 3.66), total sperm motility (MD = -0.14%, 95% CI -2.84 to 2.56), progressive sperm motility (MD = -1.06%, 95% CI -2.88 to 0.77), total sperm count (MD = 5.92 million, 95% CI -10.22 to 22.05), total motile sperm count (MD = 2.18 million, 95% CI -1.28 to 5.63), total progressively motile sperm count (MD = -3.87 million, 95% CI -13.16 to 5.43), and sperm morphology (MD = 0.07%, 95% CI -0.84 to 0.97). The results also remained similar across messenger ribonucleic acid, viral-vector, and inactivated COVID-19 vaccines. Sensitivity analysis identified two individual studies that contributed to heterogeneity, while the effect size was not materially altered. No obvious publication bias was detected among included studies. Our finding suggested that COVID-19 vaccination had no detrimental impact on semen quality, which could be potentially helpful to reduce male vaccine hesitancy and increase vaccination coverage.

The Effect of Long COVID-19 Infection and Vaccination on Male Fertility; A Narrative Review

Earlier research has suggested that the male reproductive system could be particularly vulnerable to SARS-CoV-2 (COVID-19) infection, and infections involving this novel disease not only pose serious health threats but could also cause male infertility. Data from multi-organ research during the recent outbreak indicate that male infertility might not be diagnosed as a possible consequence of COVID-19 infection. Several review papers have summarized the etiology factors on male fertility, but to date no review paper has been published defining the effect of COVID-19 infection on male fertility. Therefore, the aim of this study is to review the published scientific evidence regarding male fertility potential, the risk of infertility during the COVID-19 pandemic, and the impact of COVID-19 vaccination on the male reproductive system. The effects of COVID-19 infection and the subsequent vaccination on seminal fluid, sperm count, sperm motility, sperm morphology, sperm viability, testes and sex hormones are particularly reviewed.

The impact of COVID-19 vaccines on fertility-A systematic review and meta-analysis

BACKGROUND

Despite literature's evidence about COVID-19 vaccines' safety, concerns have arisen regarding adverse events, including the possible impact on fertility, accentuated by misinformation and anti-vaccine campaigns. The present study aims to answer the question: Is there any impact of COVID-19 vaccines on the fertility of men and women of reproductive age?

METHODS

PubMed, Scopus, Web of Science, Cochrane and Embase databases were searched for eligible studies until June 8th, 2022. The search was restricted to articles regarding humans, published in any languages, without additional restrictions. Studies' quality was assessed by the Newcastle-Ottawa and the Before and After Quality Assessment scales for cohort and pre-post studies, respectively. Random-effect meta-analyses were performed for parameters considered in ≥ 2 studies, calculating means, p-values and 95 % Confidence Intervals (CIs).

RESULTS

Out of 1406 studies screened, 29 were included in the systematic review. These studies, conducted in Israel (34.5 %), USA (24.1 %), Russia (20.7 %) China (10.3 %), Italy (3.5 %), North America (3.5%) and Turkey (3.5 %) were of poor (34.5 %), moderate (58.6 %) and good (6.9 %) quality. Meta-analyses were performed for pre- and post-vaccination sperm progressive motility (44 %, 95 % CI 42 %-62 % vs 43 %, 95 % CI 31 %-59 % p = 0.07) and concentration (50.6 mln/ml, 95 % CI 35.1-72.8 vs 55.4 mln/ml, 95 % CI 37.4-82.2p = 0.12). Biochemical (0.51, 95 % CI 0.40-0.66 vs 0.60, 95 % CI 0.53-0.68p = 0.45) and clinical (0.45, 95 % CI 0.37-0.54 vs 0.47, 95 % CI 0.40-0.55 p = 0.31) pregnancy rate did not differ among vaccinated and not vaccinated groups. Subgroup meta-analyses based on the type of vaccine showed no significant difference: between vaccinated with mRNA vaccines and non-vaccinated regarding biochemical pregnancy rates; pre- and post-vaccination with Gam-COVID-Vac regarding testosterone, FSH and LH levels; pre- and post-vaccination with BNT162b2 vaccines regarding sperm volumes.

CONCLUSION

Based on the studies published so far, there is no scientific proof of any association between COVID-19 vaccines and fertility impairment in men or women.

Semen characteristics of individuals before and after CovishieldTM vaccination

Concern about fertility impairment after vaccination is one of the reasons for vaccine hesitancy in the population. This retrospective observational study aims to understand the impact of CovishieldTM (ChAdOx1 nCoV- 19 Corona Virus Vaccine, Recombinant) COVID-19 vaccination on ejaculate quality in fifty-three patients undergoing semen analysis between 2018 to 2021. A baseline semen profile was recorded from the subjects during their visit before the vaccination for fertility work-up. Follow-up ejaculates were provided approximately 82 (Q1:37, Q3:124) days after the second dose of vaccination. Semen characteristics such as volume, sperm concentration, sperm motility, and morphological abnormalities were recorded. Of the 53 subjects, 33 (62%) had semen characteristics above the WHO reference. In general, no significant variations in the semen parameters were observed except for a moderate decline in sperm morphology (p< 0.05). The baseline semen characteristics in 20 (38%) subjects were below the WHO reference range; however, no significant decline in the ejaculate quality was observed in their follow-up samples. Further, none of the ejaculates in both study groups were azoospermic during the follow-up evaluation. Our results affirm that CovishieldTM vaccine is not detrimental to male fertility.

Effects of Covid-19 vaccination on different semen parameters

Background

The possible effects of COVID-19 vaccines on reproductive health and male fertility in particular have been discussed intensely by the scientific community and the public since their introduction during the pandemic. On news outlets and social media platforms, many claims have been raised regarding the deleterious effects of COVID-19 vaccines on sperm quality without scientific evidence. In response to this emerging conflict, we designed this study to evaluate and assess the effect of the Pfizer-BioNTech mRNA COVID-19 vaccine on male fertility represented by the semen analysis parameters.

Results

Comparing the semen parameters of the participants before and after vaccination, no statistically significant effects on semen volume, pH or normal sperm concentration and morphology were shown. However, there were statistically significant differences on total sperm motility (P = 0.05) and progressive motility (P = 0.02). These differences are clinically insignificant given the fact that both readings before and after vaccination were within the normal ranges, according to the WHO manual guidelines for the examination and processing of human semen.

Conclusion

Our data suggest that the Pfizer-BioNTech mRNA COVID-19 vaccine has no deleterious effects on semen parameters.

Covid-19 vaccination BNT162b2 temporarily impairs semen concentration and total motile count among semen donors

BACKGROUND

The development of covid-19 vaccinations represents a notable scientific achievement. Nevertheless, concerns have been raised regarding their possible detrimental impact on male fertility OBJECTIVE: To investigate the effect of covid-19 BNT162b2 (Pfizer) vaccine on semen parameters among semen donors (SD).

METHODS

Thirty-seven SD from three sperm banks that provided 216 samples were included in that retrospective longitudinal multicenter cohort study. BNT162b2 vaccination included two doses, and vaccination completion was scheduled 7 days after the second dose. The study included four phases: T0 - pre-vaccination baseline control, which encompassed 1-2 initial samples per SD; T1, T2 and T3 - short, intermediate, and long terms evaluations, respectively. Each included 1-3 semen samples per donor provided 15-45, 75-125 and over 145 days after vaccination completion, respectively. The primary endpoints were semen parameters. Three statistical analyses were conducted: (1) generalized estimated equation model; (2) first sample and (3) samples' mean of each donor per period were compared to T0.

RESULTS

Repetitive measurements revealed -15.4% sperm concentration decrease on T2 (CI -25.5%-3.9%, p = 0.01) leading to total motile count 22.1% reduction (CI -35% - -6.6%, p = 0.007) compared to T0. Similarly, analysis of first semen sample only and samples' mean per donor resulted in concentration and total motile count (TMC) reductions on T2 compared to T0 - median decline of 12 million/ml and 31.2 million motile spermatozoa, respectively (p = 0.02 and 0.002 respectively) on first sample evaluation and median decline of 9.5 × 10⁶ and 27.3 million motile spermatozoa (p = 0.004 and 0.003, respectively) on samples' mean examination. T3 evaluation demonstrated overall recovery without. Semen volume and sperm motility were not impaired.

DISCUSSION

This longitudinal study focused on SD demonstrates selective temporary sperm concentration and TMC deterioration 3 months after vaccination followed by later recovery verified by diverse statistical analyses.

CONCLUSIONS

Systemic immune response after BNT162b2 vaccine is a reasonable cause for transient semen concentration and TMC decline. Long-term prognosis remains good.

Endocrine system after 2 years of COVID-19 vaccines: A narrative review of the literature

PURPOSE

The purpose of this study was to describe the current knowledge on the potential endocrine adverse effects post-COVID-19 vaccines.

METHODS

A PubMed/MEDLINE, Web of Science, and Scopus research was performed. Case reports, case series, original studies, and reviews written in English and published online up to 31 July 2022 were selected and reviewed. The final reference list was defined based on the relevance of each paper to the scope of this review.

RESULTS

The available data showed that endocrine side effects are generally rare and with favorable outcome, being thyroid disorders the most common. Conversely, data on type 1 diabetes mellitus are rare; adrenal and pituitary events are even anecdotal. Finally, the available clinical studies suggest no impact on female reproductive system and on male and couple fertility.

CONCLUSION

Overall, these data show that, after 2 years of COVID-19 vaccines, the endocrine system is not heavily threatened.