Study of the impact of COVID-19 on the reproductive function of men.

Coronavirus disease-2019 (COVID-19) is caused by an infection by
the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which uses the ACE2 receptor and the priming of the proteaseTMPRSS2 to invade human cells. Although the more important symptoms caused by COVID-19 are pneumonia related, it also causes other symptoms affecting multiple organs, such as the digestive tract. Recent studies reported that several cell types, including some of the intestine, express ACE2 and TMPRSS2, which could explain this symptomatology [1]. Based on the ACE2 and TMPRSS2 expression, the testis has been classified as at high risk of being infected by SARS-CoV-2. In fact, some COVID-19 patients suffer scrotum discomfort, which is commonly associated with viral orchitis [2,3], and unpublished studies reported reduced testosterone levels in serum from COVID-19 patients [4,5]. However, there are conflicting
reports about the presence of SARS-CoV-2 in semen from COVID-19 patients [3,6,7], arguing that SARS-CoV-2 may not invade the testis. Nonetheless, COVID-19 may disturb spermatogenesis indirectly. For instance, due to the hyperinflammatory response of the body, which has been reported to cause a multiorgan failure as a complication of the disease. Alternatively, the sustained
period of high fever caused by the infection may also impair spermatogenesis [8,9].