The JAMA study came amid a rise in vaccine hesitancy amid the quick rollout of the vaccine and potential repercussions such as fertility issues.
The participants were prescreened prior to the study to ensure there were no underlying issues and also tested for coronavirus multiple times. The men were tested before and after each dose of the vaccine. The 45 volunteers, aged 18 to 50, showed no significant decreases in any sperm parameter, the study said.
“Because the vaccines contain mRNA and not the live virus, it is unlikely that the vaccine would affect sperm parameters,” the study said.
The study comes as states implementing incentives like million-dollar prizes, free beer and countless other giveaways around the country have failed to significantly move the needle on vaccine hesitancy.
The pace of new vaccinations in the U.S. has dropped below 400,000 people per day — down from a high of nearly 2 million per day two months ago.
To date 64.7% of the adult U.S. population have received at least one dose of a COVID-19 vaccine and 141.5 million are fully vaccinated, according to Centers for Disease Control and Prevention data.