University of Miami Miller School of Medicine is the first institution studying the effects on sperm of men who receive the vaccine, according to the study’s principal investigator, Ranjith Ramasamy, M.D., associate professor and director of reproductive urology.
“Based on the mechanism by which mRNA acts, we do not expect the COVID-19 vaccines will have an impact on male fertility. But obviously we want data to confirm that hypothesis,” Dr. Ramasamy said.
The Miller School is recruiting men ages 18 to 50 years old who are scheduled to get the COVID-19 vaccine.
“We are going to evaluate sperm production and sperm quality for men who are thinking about fertility either at present or in the future and will receive the COVID-19 vaccine,” said Daniel Nassau, M.D., a urology fellow at the Miller School who helped spearhead the study. “We want to see if there is any decrease in sperm production or quality. We will look at a semen sample before they get the vaccine and then at three and six months thereafter.”
Conducting such a study is important for a public that’s eager for information about the COVID vaccine, which has been approved by the Food and Drug Administration (FDA) under Emergency Use Authorization.
“It is very important that everyone in America and around the world receive the vaccine for COVID-19,” Dr. Nassau said. “We are hoping and think this study will help confirm the vaccine’s safety in terms of male fertility.”
The FDA’s Emergency Use Authorization for the Pfizer vaccine means that it has been evaluated and shown to be safe and effective. The Moderna vaccine, for which the Miller School was a clinical trial site, is currently under review by an FDA panel. To gain approval, any vaccine must have been tested in large clinical trials, scientifically showing that it is indeed safe and efficacious against the coronavirus.
Because the vaccine was approved under Emergency Use Authorization, it is not mandatory for health care workers or others.
“That is why we are doing this study, to go back and test the vaccine for safety in male fertility so it can educate, and possibly reassure, the public,” Dr. Ramasamy said. “The companies providing the vaccine can then use this and other data to possibly move forward with the FDA’s full authorization for use.”
The Miller School researchers anticipate that they will have at least preliminary data by the time most of the population is able to get the vaccine, around spring 2021.
Dr. Ramasamy and colleagues at the Miller School are studying the impact of COVID-19 on sperm and have found the virus, itself, impacts sperm quality.
“Our group and others have confirmed that the COVID-19 virus can affect sperm production inside the testes. We have shown that long after the infection is gone and when men who have had the virus become asymptomatic, the virus can continue to linger inside the testes,” Dr. Ramasamy said. “So, I think the question on how COVID-19 affects fertility remains to be answered and certainly is worthy of exploration in future studies.”
More information on the COVID-19 vaccine study on male fertility is available here: https://www.clinicaltrials.gov/ct2/show/NCT04665258