Covid-19 vaccines

A new study has shown that Covid-19 vaccines do not cause infertility in men. 

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Covid-19 vaccines have no effect on fertility, study reveals 

What you need to know:

  • There has been a lot of misinformation on social media regarding the effect of the vaccines on fertility.
  • The uptake of vaccines across the world has been hampered by the misinformation.

Covid-19 vaccines do not reduce the quality of sperms and have no negative effect on fertility, findings from a new study have revealed.

Since the country started vaccinating people, there has been a lot of misinformation on social media regarding the effect of the vaccines on fertility, with claims that they can interfere with the sperm count.

However, a study published on Thursday in the Journal of the American Medical Association (JAMA) on 45 young and sexually active men between the ages of 25 and 31 who received Pfizer or Moderna vaccines revealed that there were no significant decreases in any sperm parameter before and after two doses of the vaccines.

“It is unlikely that the vaccine would affect sperm parameters. While these results showed statistically significant increases in all sperm parameters, even men with oligospermia (low sperm count) did not experience further decline,” says the study.

The men were pre-screened to make sure they had no fertility issues. Samples were taken before the first shot, then 70 days after the second dose. Semen was then examined to determine sperm volume, concentration, motility and total sperm count.

According to the study, many people do not want to receive the Covid-19 vaccine because of the myth that they have a potential negative effect on fertility.

The single-centre prospective study at the University of Miami ensured that the participants provided a semen sample after two to seven days of abstinence, prior to receiving the first vaccine dose and approximately 70 days after the second.

Sperm count

Semen analyses were performed by trained andrologists as per World Health Organization guidelines and included semen volume, sperm concentration, sperm motility, and total motile sperm count. 

Those with Covid-19 symptoms or a positive test result within 90 days were excluded, however, individuals with oligospermia – a sperm concentration of less than 15 million per milliliter -- were included. 

After the end of the study, baseline samples were obtained after abstinence of three days and follow-up samples after three days.

Of the 45 men, 21 (47 per cent) received Moderna and 24 (53 per cent) received Pfizer. Baseline sperm concentration was 26 million/Ml. After the second vaccine dose, the median sperm concentration significantly increased to 30 million/mL 

Semen volume and sperm motility also significantly increased.

Eight of the 45 men were oligospermic before the vaccine with a median sperm concentration of 8.5 million/mL, of these eight, seven men had increased sperm concentration to normozoospermic of a median concentration of 22 million/mL while one man remained oligospermic. 

No man became azoospermic after the vaccine. Azoospermia is a condition in which there's no measurable sperm in a man's semen.

Sperm quality

"This is enough evidence that should reassure you that the Covid-19 vaccines do not compromise your sperm count," said Dr David Cohen, co-medical director of the Institute for Human Reproduction in Chicago, who was not involved in the study. 

"This is reassuring data, which suggests that sperm quality is not significantly altered by receiving two doses of one of the new vaccines for Covid-19," said Allan Pacey, professor of andrology at the University of Sheffield in the UK.

“With the results, we need to do this in a larger population,” Dr Cohen said.

According to Dr Patrick Amoth, the acting director general in the Ministry of Health, misinformation is one of the factors hindering the uptake of Covid-19 vaccine.

“Until you are informed by researchers or a study done, then people should treat it as a rumour, we also need to do the research in our population, though he clarified that proven vaccines cannot cause infertility or reduction in sperm count,” Dr Amoth said.

While the vaccine had no impact on sperms, the virus itself could be harmful to the male reproductive tract, according to a small study published in January.

Compared to healthy men without Covid-19, the study found a significant increase in inflammation and oxidative stress in sperm cells belonging to men with Covid-19. Their sperm concentration, mobility and shape were also negatively impacted by the virus.