Research counters Nicki Minaj’s tweet about COVID-19 vaccines and impotency

UPDATES, Sept. 15, 5:15 p.m.: We added new comments at the end of this story from the minister of health in Trinidad and Tobago, who refuted Minaj’s claims.

 On Sept. 13, Nicki Minaj tweeted that she wasn’t vaccinated against COVID-19, and that if she does get vaccinated, it won’t be until she feels like she’s "done enough research." 

About 20 minutes later, the Trinidadian-born rapper tweeted again about the vaccine and offered some insight into why, perhaps, she’s wary of it. 

"My cousin in Trinidad won’t get the vaccine cuz his friend got it & became impotent," she said. "His testicles became swollen. His friend was weeks away from getting married, now the girl called off the wedding. So just pray on it & make sure you’re comfortable with ur decision, not bullied."

Back in May, we looked into misinformation about how the COVID-19 vaccine affects sperm production. In short, research from the University of Miami was being misrepresented to claim that the vaccines affected sperm production. In reality, the researchers had been looking at the effects of COVID-19, not vaccines against the disease. 

At the time, Dr. Daniel Nassau, who worked on that study as a fellow and investigator with lead author Dr. Ranjith Ramasamy, told us that researchers at the university’s Miller School of Medicine were separately investigating how mRNA vaccines may affect fertility. 

"We do not think the vaccine will affect male fertility," he told PolitiFact, but researchers were still waiting for the results of the study to be published. 

That research is now online on the Journal of the American Medical Association website. After recruiting 45 healthy men between the ages of 18 and 50 with no underlying fertility issues, researchers collected semen samples before they received their first COVID-19 vaccine dose and approximately 70 days after they received their second dose. 

The results? 

"We found that there were no negative impacts of the vaccine on male fertility," Nassau said.

In fact, the research showed "statistically significant increases in all sperm parameters," though that change was within normal variations and could be because of how long the men were abstaining from sex before the second sample was taken. 

The research only looks at a small number of men and "is an imperfect predictor of fertility potential," according to the work published on JAMA’s site.

Still, Nassau told us, "there are no reports about vaccine causing erectile dysfunction or orchitis," an inflammation of one or both testicles. 

However, he said, data has suggested that a COVID-19 infection itself may be a risk factor for impotence and male infertility, and it has been found to cause orchitis in up to 22% of men. 

As for Minaj’s claim, "I saw the tweet," Nassau said. "I am certain what she is describing is not related to a COVID-19 vaccine." 

The minister of health in Trinidad and Tobago, Terrence Deyalsingh, responded on Sept. 15 to Minaj’s claim.

"Unfortunately it wasted so much time yesterday running down this false claim," Deyalsingh said. "As far as we know at this point in time there has been no such reported side effect or adverse event."

Deyalsingh added that there are no such side effects "anywhere in the world" that he and other health officials know of.