Impact of COVID-19 vaccination on seminal and systemic inflammation in men

Expedited development of SARS-CoV-2 vaccines led to public concerns regarding impacts of the novel vaccine on gametes in patients seeking assisted reproduction. In cases of an acute intermittent illness or fever in men, it is often advised to postpone ART treatments so that efforts can be made to enhance wellbeing and improve sperm parameters. However, it is unknown whether sperm parameters are altered in the acute (24-72 hour) phase following COVID-19 vaccination. We performed a longitudinal cohort study of 17 normospermic male patients attending a fertility clinic for semen analysis. Semen and matched peripheral blood samples were collected prior to vaccination, within 46 + 18.9 hours of vaccine course completion (acute) and at 88.4 + 12 days (3 months) post-vaccination. No overall change from baseline was seen in symptoms, mean volume, pH, sperm concentration, motility, morphology or DNA damage in the acute or long phase. Seminal plasma was found to be negative for anti-SARS-CoV2 Spike antibody detection, and MCP-1 levels showed an acute but transient elevation post-vaccine, while IL-8 was marginally increased 3 months after completion of vaccination. A modest, positive correlation was noted between serum levels of the anti-inflammatory cytokine IL-10 and self-reported symptoms post-vaccine. Our findings are reassuring in that no significant adverse effect of vaccination was noted and provide evidence to support the current recommendations of reproductive medicine organisations regarding timing of vaccination during fertility treatment.