Effect of SARS-CoV-2 on semen parameters: A meta-analysis of 39 articles from 15 countries.

Background: Declining birth rates during the pandemic have led to concerns about the potential impact of the of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on fertility among men. As previous studies have had inconsistent conclusions, we conducted a meta-analysis to evaluate the effects of SARS-CoV-2 on semen parameters.

Methods: We searched several databases for articles published between 1 January 2020 and 25 July 2023. We performed a robust screening process based on predetermined inclusion and exclusion criteria and, following quality assessment, extracted data from high-quality studies for the meta-analysis. We determined the P-values and 95% confidence intervals (CIs) for both continuous and dichotomous variables, which we described using mean differences (MDs) and odds ratios (ORs), respectively. Lastly, we used the leave-one-out approach for our sensitivity analysis, and Begg's and Egger's tests to determine publication bias.

Results: We included 39 articles with 1887 cases and 2097 controls. In patients infected with SARS-CoV-2, the sperm volume (MD = -0.29; 95% CI = -0.50, -0.07; P = 0.008) and concentration (MD = -8.71; 95% CI = -16.94, -0.48; P = 0.04) were decreased, which increased oligospermia risk (OR = 2.49; 95% CI = 1.04, 5.99; P = 0.04). Furthermore, we observed reduced sperm motility (MD = -8.18; 95% CI = -12.19, -4.17; P < 0.001) and increased immotility (MD = 4.06; 95% CI = 1.57, 6.54; P = 0.001) in infected patients, which increased asthenospermia risk (OR = 3.86; 95%CI = 1.83, 8.14; P = 0.0004). We also saw a decreased proportion of semen with normal sperm morphology (MD = -1.67; 95% CI = -2.68, -0.66; P = 0.001) and an increased proportion of semen with abnormal sperm morphology (MD = -1.31; 95% CI = -2.14, -0.49; P = 0.002,), along with increases in teratospermia (OR = 1.98; 95% CI = 1.00, 3.92; P = 0.05) in infected compared non-infected patients. Although we found consistency within most subgroups, we observed differences in severity, follow-up time, and country of origin. The results of the main meta-analysis results remained stable in the sensitivity analysis, while Begg's and Egger's tests showed no publication bias.

Conclusions: Based on sufficient evidence, we see that the effects of SARS-CoV-2 on semen parameters resulted in a decline in male fertility. The increased severity and shorter duration of the SARS-CoV-2 infection increased the likelihood of altering of semen parameters.

Registration: INPLASY: INPLASY202420083.