What is the recovery time for sperm parameters in men who have suffered a mild Covid-19 infection?
Núñez-Calonge R (Speaker), Guijarro Ponce J, Rubio T, Alberola P, Fernández G, Santamaría N, Alonso S, Barros I
Study question:
What is the time required in men who have suffered a mild Covid-19 infection, for the seminal parameters to be restored to the pre-Covid values?
Summary answer:
The effect of Covid-19 infection on the concentration and sperm motility is clearly confirmed and is maintained over time, at least beyond 100 days.
What is known already:
Although several studies have been performed on the effect of SARS-CoV-2 on reproductive health in the short term vs. healthy controls, and the negative effect on sperm parameters has been demonstrated, there is a scarcity of data showing the degree to which the virus affects the semen parameters in one group of patients after coronavirus infection compared to before infection. Moreover, there are no conclusive data regarding the long-term effects of SARS-CoV-2 on semen parameters.
Study design, size, duration:
This prospective study was carried out in 6 reproductive centers between February 2020 and October 2022 including 45 male patients with a confirmed diagnosis of mild COVID-19. For each of the semen parameters (volume, sperm count, active and total motility, normal morphology, and vitality) a standardized index was calculated by dividing the value of the parameter from the subsequent semen analysis by that from the semen analysis of the same individual prior to infection.
Participants/materials, setting, methods:
The median age of the participants was 31 years, proving the absence of a relationship between age and any of the parameters analyzed.
The post-Covid test was performed between 17 and 516 days after infection, with a median of 100 days. The time elapsed between both samples was a median of 238 days. The effect of time on the affectation of semen parameters was studied, setting 100 days as the cut-off point.
Main results and the role of chance:
There were significant differences in semen parameters before and after COVID-19 in terms of semen volume, sperm concentration, progressive motility, total motility, and vitality which decreased significantly (p<0,05) after SARS-CoV-2 infection compared to the pre-infection values. Morphology was not significantly affected. The total sperm count is the most clearly affected seminal parameter. Half of the individuals (median) obtained a total count in the second sample less than 57% of the initial one.
Considering the time of spermatogenesis, the subjects were separated into two groups: those who performed the semen analysis in the first 100 days after infection and those who performed it later. No differences in any parameter were found between the two groups with U Mann-Withney test. Using the Wilcoxon test for paired samples, it was demonstrated that the deleterious effect of infection on sperm concentration and motility not only does not improve with time, but it becomes more significant in late sperm analysis, performed more than one hundred days after the infection.
Limitations, reasons for caution
It should be mentioned that impairment of semen parameters may not be due to a direct effect of the SARS-CoV-2 virus. There are likely to be additional factors that contribute to long-term sperm parameters decrease, but whose identity is currently unknown.
Wider implications of the findings:
The present study revealed the long-term impacts of SARS-CoV-2 on various parameters of sperm quality even with a mild infection. Further efforts should be made to study the long-time effects of COVID-19 infection on male reproduction.
