COVID-19 Infection May Affect Male Fertility, While Vaccination Shows No Harm: Study
Seasonal Covid-19 Uptick Prompts Precautionary Measures Across India
An umbrella review of 14 studies evaluating 40 fertility and assisted reproductive technology (ART) outcomes found that COVID-19 infection may significantly impair male reproductive health, potentially affecting sperm quality and related parameters. In contrast, female fertility and ART outcomes appeared largely unaffected by COVID-19 infection. Importantly, COVID-19 vaccination showed minimal to no negative impact on fertility or ART outcomes in either men or women, supporting its safety in individuals concerned about reproductive health. The study was published in the Vaccine journal by Qi Cao and colleagues.
Infection with SARS-CoV-2 mainly affects male fertility by decreasing sperm quality, concentration, and motility, whereas female fertility and ART outcomes remain unaffected. Conversely, COVID-19 vaccination has a negligible effect on fertility in both males and females. Since the emergence of the COVID-19 pandemic, there have been concerns about the long-term effects of the virus on reproductive health.
The mechanisms postulated for the effects of SARS-CoV-2 infection on fertility include direct viral effects and systemic inflammation. To address the question of the effects of SARS-CoV-2 infection and vaccination on fertility in males and females, as well as ART outcomes, an umbrella review of meta-analyses was undertaken.
The search for studies was conducted on major databases until December 30, 2023. Of the 647 studies retrieved, 14 meta-analyses involving 40 outcomes were considered in the final analysis. The quality of evidence was assessed using the Measurement Tool to Assess Systematic Reviews and the Grading of Recommendations, Assessment, Development, and Evaluation approach. The quality of evidence for the outcomes was graded as very low to low, and the need for higher quality prospective studies was emphasized.
Key findings
The results showed that COVID-19 infection may significantly reduce semen quality in men. The weighted mean differences (WMD) and standardized mean differences (SMD) showed measurable declines across several parameters:
Semen volume: WMD −0.48 ml (95% CI, −0.59 to −0.36 ml)
Total sperm count: WMD −34.84 × 10^6 (95% CI, −43.51 to −26.17 × 10^6)
Sperm concentration: WMD −16.23 × 10^6/ml (95% CI, −25.56 × 10^6 to −6.89 × 10^6)
Sperm viability: SMD −0.66 (95% CI, −1.27 to −0.06)
Total sperm motility: SMD −0.61 (95% CI, −0.96 to −0.25)
Estradiol levels were elevated (SMD 0.652; 95% CI, 0.254 to 1.049; p = 0.001), as were prolactin levels (SMD 0.305; 95% CI, 0.045 to 0.566; p = 0.022).
Vaccination had minimal impact on fertility parameters in both sexes. Evidence quality was rated very low to low.
The infection caused by SARS-CoV-2 seems to have a predominantly adverse effect on male fertility, resulting in a significant reduction in the quality, count, and motility of sperm, whereas female fertility and assisted reproduction techniques are found to be unaffected. The COVID-19 vaccine has been found to have minimal effects on reproductive health in both males and females. Due to the low certainty of evidence, further high-quality prospective studies are required to understand the actual extent of these effects.
Reference:
Cao, Q., Du, S., Yang, K., Liu, M., Xiao, L., Wang, Q., Fu, J., & Zhu, H. (2026). Assessing the impact of SARS-CoV-2 infection and vaccination on fertility and assisted reproductive techniques outcomes: an umbrella review. Vaccine, 76(128293), 128293. https://doi.org/10.1016/j.vaccine.2026.128293
