Sperm count not affected by COVID-19 vaccine, study finds

A recent study aims to decrease COVID-19 vaccine hesitancy in men after revealing that Pfizer/BioNTech and Moderna vaccines don’t harm sperm count or quality.

Scientists at the University of Miami published their findings this month in JAMA

The study involved 45 healthy men between 25 and 31 years old. The men provided a semen sample before getting the first COVID-19 vaccine and then another sample nearly 70 days after getting the second dose.

Scientists tested for semen volume, sperm concentration, sperm motility and total motile sperm count.

Results found "no significant decreases in any sperm parameter among this small cohort of healthy men." In fact, the study revealed that some men saw increases in their sperm parameters. Doctors believe that it was due in part to their prolonged abstinence, which was a condition of the study, or the normal variation commonly seen in men. 

RELATED: NIH testing effectiveness, safety of mixing COVID-19 vaccines with potential boosters

However, doctors pointed out the study's shortcomings, saying they only sampled a small number of men. They also didn’t have a control group and the follow-up period was short. Despite this, doctors said the study's time frame did involve the full life-cycle of a sperm. 

The study did not include any men who had received the one-dose Johnson & Johnson vaccine.

There had been some concern that the COVID-19 vaccine could potentially affect male fertility after speculation started to grow on social media. 

In a study published in The World Journal of Men’s Health, researchers found that COVID-19 can invade testis tissue in some men who are infected with the virus. The belief that COVID-19 could enter the male reproductive organs may indicate that the virus could be transmitted sexually, according to the study’s lead author, Dr. Ranjith Ramasamy, associate professor and director of reproductive urology at the Miller School.

However, in January, the Society for Male Reproduction and Urology released a statement saying the COVID-19 vaccine doesn’t affect fertility and recommends men to get the vaccine if they’re eligible.

Vaccine hesitancy still remains a problem as the vaccination rate slows in the U.S. 

According to the U.S. Centers for Disease Control and Prevention, more than 149 million Americans have been fully vaccinated, representing 44.9% of the country’s total population. 

RELATED: Slowed COVID-19 vaccinations endanger Biden’s July 4 goal

CDC data shows the country is averaging fewer than 1 million shots per day. That’s far below April’s peak when the country was averaging more than 3 million shots a day. 

Dangling everything from sports tickets to a free beer, Biden is looking for that extra something — anything — that will get people to roll up their sleeves for COVID-19 shots.

Additionally, the White House is partnering with early childhood centers such as KinderCare, Learning Care Group, Bright Horizons and more than 500 YMCAs to provide free childcare coverage for Americans looking for shots or needing assistance while recovering from side effects.

Biden’s plan will continue to use public and private-sector partnerships, mirroring the "whole of government" effort he deployed to make vaccines more widely available after he took office. The president said he was "pulling out all the stops" to drive up the vaccination rate.

The Associated Press contributed to this report. This story was reported from Los Angeles.