Table 1 Studies reporting the relation between COVID-19 and possible infectivity through semen and sexual transmission

Pan et al. [21]

Observational, cross-sectional study

34 (adult male)

1. SARS–CoV-2 was not detected in the semen of enlisted patients recovering even a month after COVID-19 diagnosis.

2. ACE-2 receptor-mediated SARS-CoV-2 entry into target host cells is unlikely to prevail within the human testis.

Nora et al. [23]

Pilot cohort study

34 (adult male)

1. Function of testis and epididymis was not likely affected by a mild COVID-19 infection, whereas semen parameter analysis seems to be impaired after a moderate infection.

2. Detection of SARS-CoV-2 RNA showed negative in semen of recovered individuals and acute COVID-19 positive patients, suggesting no viral transmission during sexual behavior as well as when performing the assisted reproductive techniques (ART).

Li et al. [22]

Cohort study

Out of total 50 patients, 38 patients were enrolled for semen testing (men of 15 years and above)

Six patients (15.8%) of total 38 resulted positive for SARS-CoV-2 from semen samples.

But no significant differences were observed between negative and positive test results in respect to age, disease history of urinary or genital tract, days since onset, days since hospitalization, or days since clinical recovery.

Song et al. [20]

Descriptive study

Total 13 patients (including one patient who died in COVID-19 infection) (12 patients with age group 22 to 38 years. One patient with age 67 who died in COVID-19 infection)

All of the patients tested negative for SARS-CoV-2 RNA in collected semen samples as well as testicular biopsy (for the dead patient) concluding the absence of sexual transmission property of SARS-CoV-2 from male.

Segars et al. [24]

Systematic review and meta-analysis

79 articles were included out of 663 articles.

Reports of this article indicated the reduced sperm concentration and motility for 72–90 days following SARS-CoV-2 infection.

Paoli et al. [25]

Case study

One (31 years old)

Semen and urine samples appeared as negative for the presence of SARS-CoV-2 RNA.

Ma et al. [26]

Case control study

81 reproductive-aged men with SARS-CoV-2 infection and 100 age-matched healthy men

This study explained the direct evidence for the severity of SARS-CoV-2 infection on male sex hormones, alerting more curiosity to gonadal function evaluation among those patients recovered from SARS-CoV-2 infection, especially the reproductive-aged men.

Li et al. [27]

Case-controlled study

Autopsied testicular and epididymal specimens of deceased (n=6) and recovering (n=23) COVID-19 male patients with an equal number of age-matched controls.

Among the COVID-19 patients, a spermatogenic dysfunction was observed, which could be due to a sequel of elevated immune response in testis. Besides autoimmune orchitis, which was recorded in a couple of COVID-19 patients.

Kayaaslan et al. [28]

Cohort study

Patients with acute-stage of COVID-19 infection (n =16)

SARS-CoV-2 RNA was not detected in semen. Decreased serum FSH, LH, and testosterone levels have been found in COVID-19 group compared to controls; significant reduced sperm morphology in COVID-19 group compared to controls; no significant differences between groups after treatment.

Guo et al. [29]

Cohort study

COVID-19 patients in acute and recovery phase (n=23)

SARS-CoV-2 RNA was not detected in semen

Temiz et al. [30]

Case-controlled study

Control (n=10), COVID-19 pre-treatment (n=10) and post-treatment (n=10)

No SARS-CoV-2 RNA detected in semen.

Gacci et al. [31]

Cohort study

Sexually active men recovered from COVID-19 (n=43)

SARS-CoV-2 RNA detected in semen of one patient. 25% found to be oligo-crypto-azoospermic that was related to COVID-19 severity; 76% found to have increased seminal IL-8.

Ruan et al. [32]

Case-controlled study

Patients recovering from COVID-19 (n=74). Age-matched healthy controls (n=174)

No SARS-CoV-2 RNA detected in semen or urine. Significantly reduced sperm concentration, total sperm count, and total motility compared controls.