The Effect of BNT162b2 mRNA COVID-19 Vaccine on Semen Analysis Parameters Among 75 Fertile Men

The 2019 novel coronavirus disease (COVID-19) is a highly infectious respiratory tract disease which was first reported in Wuhan, Hubei Province, China in Dec 2019, but has since spread globally. By march 2020 it was declared by WHO as a public health emergency pandemic and has thus far affected tens of millions worldwide. The implications of COVID 19 infection on male fertility were examined in a previous study, which found decreased sperm concentration in recovering patients compared with controls.

The newly available mRNA COVID 19 vaccine by Pfizer was recently evaluated in a large multicenter placebo controlled RCT. The vaccine is comprised of BNT162b2, a lipid nanoparticle formulated nucleoside-modified RNA (modRNA) encoding the SARS-CoV2 full length spike protein, modified by two Proline mutations. The two 20 µg doses were shown to elicit high SARS-COV2 neutralizing antibody titers alongside high antigen specific CD8+ and Th1 type CD4+ T cell response. It was subsequently shown to be 95% effective in preventing COVID-19 infection a week following the second dose with a favorable safety profile in a 2-month median following up time.

Unfounded claims in the popular media linked a possible correlation between the COVID-19 vaccine and potential female\male infertility. Currently. there is no information in the medical literature which examined semen analysis parameters following the COVD-19 vaccine.

In this study the investigators will explore the effect of the BNT162b2 COVID-19 Vaccine on semen analysis parameters among 75 fertile men. Fertile men will be regarded as such if they previously successfully impregnated their partners without the use of artificial reproductive technology, or men who previously had a normal sperm analysis exam by WHO criteria (2010). Those recruited will supply a single sperm sample 1-2 months following the second dose of the vaccination. In addition, the participants will fill a brief questionnaire with information regarding their medical and reproductive history. The investigators will examine the macroscopic and microscopic properties of the semen samples and compare them to the WHO semen analysis reference range in an attempt to ascertain whether the vaccine influences sperm parameters.