Get a load of whats being said about the Covid-19 vaccines now. Some social media accounts have been claiming that Covid-19 vaccines could cause mass male infertility and that all males who have been vaccinated are effectively sterile. Its not clear who exactly is behind many of these social media accounts and how much of this may be artificial dissemination. Nonetheless, these claims dont semen to be accompanied by much real supporting evidence. And now a study just published as a research letter in JAMA has come out with some more evidence to address any premature speculation about vaccines and male fertility.

This study examined the semen of men before and after they got Covid-19 mRNA vaccines. Now semen isnt a bunch of people on boats. Instead, its a bunch of spermatozoa, or sperm if you dont have enough time to say atozoa, suspended in fluid. A team from the University of Miami (Daniel C. Gonzalez; Daniel E. Nassau, MD; Kajal Khodamoradi, PhD; Emad Ibrahim, MD; Ruben Blachman-Braun, MD; Jesse Ory, MD; Ranjith Ramasamy, MD) conducted this study. They used the following four commonly used measures of male fertility:

From December 17, 2020, to January 12, 2021, the research team managed to recruit 45 men to lend a hand or two to the study. These study participants ranged in age from 18 to 50 years of age with a median age of 28. Each was already scheduled to get either the Pfizer/BioNTech or the Moderna Covid-19 mRNA vaccines. At the start of the study, none of the volunteers had any underlying fertility issues or had had positive Covid-19 tests in the previous 90 days.

The researchers asked participants to provide two semen samples: one sample prior to the first Covid-19 vaccine dose and a second sample approximately 70 days after the second vaccine dose.

Were the participants able to master the request to remain abstinent before providing the samples? Somewhat. The participants had refrained from using their equipment, so to speak, a median of 2.8 days before providing the first semen sample. They were able to hold on or perhaps the more appropriate phrase is hold off for a little longer the second time around. The participants had remained abstinent a median of 3 days before providing the second semen sample.

When it came to which vaccine the participants got, things were close to even. Of the 45 men, 21 received the Pfizer/BioNTech vaccine and 24 received the Moderna vaccine.

So was there any evidence that the Covid-19 vaccines had affected the participants fertility? Well, the study did provide the participants with a sense of relief, so to speak. On average, the four measures did not drop. In fact, things went a bit up from the first to the second samples. The median sperm concentration increased from 26 million/mL to 30 million/mL, the median total motile sperm count from 36 million/mL to 44 million, semen volume from 2.2 to 2.7 mL, and sperm motility from 58% to 65%. In fact, of the eight men who had low sperm concentrations (sperm concentration <15 million/mL) at the beginning of the study, seven had their sperm concentration increase to within the normal range.

Before you rush out to get Covid-19 vaccines to increase your sperm count, keep in mind that there are other reasons why all of these measures increased. For example, remember the study participants were able to hold off a little longer from walking the penguin before providing the second sample. This could have meant that they were more on the ball the second time around to provide semen.

Of course, one small study alone is not enough prove anything. When it comes to scientific studies, size does matter. Forty five men is not huge, meaning that a study of this many men is not a huge study. Also, the follow-up was fairly short: a median of 75 days after the second dose of the vaccine. Although, this is longer than the estimated 64 day or so life cycle of a sperm. Plus, there was no control group, no comparison group that didnt get the Covid-19 vaccine. Moreover, having normal semen volumes, sperm motility, sperm concentration, and total motile sperm counts are not guarantees of fertility.

Nevertheless, this was a scientific study published in a reputable peer-reviewed scientific journal, which is more than the mass male infertility conspiracy theorists have offered, much more. Angelo Fichera detailed some more of these male infertility claims for FactCheck.org, a project of The Annenberg Public Policy Center. One example has been Roger Hodkinson, MB, a Canadian pathologist who has reportedly called Covid-19 the biggest hoax, asserting that the Covid-19 coronavirus spike protein expresses in the placenta and the testes. Ive already written before for Forbes about how this assertion is unfounded for the placenta. In the following video from the Childrens Hospital of Philadelphia (CHOP), Paul Offit, MD, Director of the Vaccine Education Center and Professor at CHOP, explains how the misconception about the placenta arose:

Similarly, the nuts and bolts of the matter is that there is no evidence that your testicles contain a protein thats similar enough to the Covid-19 coronavirus spike protein. In other words, dont be worried about your body attacking your balls after you get the Covid-19 vaccine, unless, of course, you happen to be missing badly while swinging a hockey stick.

While there is no evidence that the Covid-19 vaccine is harmful to your genitalia, studies have suggested that the Covid-19 coronavirus (not the vaccine but the virus itself) may affect your testicles, as I have covered for Forbes previously. In fact, there are also concerns that the virus may adversely affect the thing next to your balls and its ability to rise to the occasion, so to speak, as I have covered for Forbes previously as well.

So it looks like there are actually some groin reasons to get the Covid-19 vaccine, in addition to the whole prevent you from dying thing. The benefits and safety of the Covid-19 vaccine have prompted the Society for Male Reproduction and Urology (SMRU) and the Society for the Study of Male Reproduction (SSMR) to issue a joint statement recommending that:

They did add that about 16% of men in the Pfizer/BioNtech Covid-19 vaccine clinical trial experienced fever after the second dose. Fevers can cause temporary declines in sperm production. So, although some like it hot, you may want to wait until the post-vaccination fever passes before getting down to business, depending on the purpose of the business.