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COVID infection may impair male fertility, but vaccination shows no effect, review suggests
Laine Bergeson
Today at 2:43 p.m.
COVID-19
COVID-19 infection may meaningfully affect male reproductive health, while having limited consequences for female fertility or assisted reproductive technology (ART) outcomes, according to a new umbrella review published this week in Vaccine. In contrast,COVID vaccination showed little impact on fertility in either men or women.
The review, led by a team at the Department of Reproductive Medical Center at Sichuan University in Chengdu, China, assessed the effects of COVID infection and COVID vaccination on fertility and ART outcomes by analyzing data from 14 studies with 40 different fertility and ART outcomes.
Impaired male fertility persists 3 months after infection
Among men, the data suggests, COVID infection is associated with reductions in semen quality, including lower semen volume and concentration, and total sperm count, viability, and motility. COVID infection was also associated with elevated levels of the hormones estradiol and prolactin in men, though it did not appear to significantly affect testosterone levels.
These negative fertility outcomes in men persisted after infection. “Notably, even after recovery (over 90 days), sperm concentration and motility remained lower compared to uninfected individuals,” they write.
COVID infection is associated with reductions in semen quality, including lower semen volume and concentration, and total sperm count, viability, and motility.
While the authors emphasize the need for more research because the quality of the evidence in the included studies is rated low, they note the biological plausibility of COVID infection on male fertility given the high distribution of viral-entry receptors such as angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in male reproductive organs.
“Given the high expression of ACE2 and TMPRSS2 in the testes…the male reproductive system is theoretically prone to SARS-CoV-2 infection,” they write. “This infection, leading to orchitis [inflammation of the testicles] and disruption of spermatogenesis [the creation of mature sperm], might result in reduced sperm count, motility, and overall semen quality.”
No link between COVID vaccination, fertility outcomes
For women, COVID infection was not associated with negative fertility outcomes. “COVID-19 showed minimal impact on female ovarian reserve…or ART outcomes,” they write, despite ACE2 being present in ovarian tissues and the lining of the uterus, which suggests COVID infection could affect female reproductive organs and interfere with fertility.
The analysis did not find evidence of reproductive harm from COVID vaccination for either men or women.
“More high-quality prospective studies with longer follow-up periods are needed,” they write, specifying that “the findings for male reproductive impact warrant further longitudinal investigation, especially into long-term fertility and live birth outcomes.”
They also emphasize the lack of evidence showing an association between COVID vaccination and fertility outcomes. “The current evidence does not substantiate concerns linking COVID-19 vaccines to impaired fertility or ART failure,” they conclude.
COVID infection may impair male fertility, but vaccination shows no effect, review suggests
Laine Bergeson
Today at 2:43 p.m.
COVID-19
COVID-19 infection may meaningfully affect male reproductive health, while having limited consequences for female fertility or assisted reproductive technology (ART) outcomes, according to a new umbrella review published this week in Vaccine. In contrast,COVID vaccination showed little impact on fertility in either men or women.
The review, led by a team at the Department of Reproductive Medical Center at Sichuan University in Chengdu, China, assessed the effects of COVID infection and COVID vaccination on fertility and ART outcomes by analyzing data from 14 studies with 40 different fertility and ART outcomes.
Impaired male fertility persists 3 months after infection
Among men, the data suggests, COVID infection is associated with reductions in semen quality, including lower semen volume and concentration, and total sperm count, viability, and motility. COVID infection was also associated with elevated levels of the hormones estradiol and prolactin in men, though it did not appear to significantly affect testosterone levels.
These negative fertility outcomes in men persisted after infection. “Notably, even after recovery (over 90 days), sperm concentration and motility remained lower compared to uninfected individuals,” they write.
COVID infection is associated with reductions in semen quality, including lower semen volume and concentration, and total sperm count, viability, and motility.
While the authors emphasize the need for more research because the quality of the evidence in the included studies is rated low, they note the biological plausibility of COVID infection on male fertility given the high distribution of viral-entry receptors such as angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in male reproductive organs.
“Given the high expression of ACE2 and TMPRSS2 in the testes…the male reproductive system is theoretically prone to SARS-CoV-2 infection,” they write. “This infection, leading to orchitis [inflammation of the testicles] and disruption of spermatogenesis [the creation of mature sperm], might result in reduced sperm count, motility, and overall semen quality.”
No link between COVID vaccination, fertility outcomes
For women, COVID infection was not associated with negative fertility outcomes. “COVID-19 showed minimal impact on female ovarian reserve…or ART outcomes,” they write, despite ACE2 being present in ovarian tissues and the lining of the uterus, which suggests COVID infection could affect female reproductive organs and interfere with fertility.
The analysis did not find evidence of reproductive harm from COVID vaccination for either men or women.
“More high-quality prospective studies with longer follow-up periods are needed,” they write, specifying that “the findings for male reproductive impact warrant further longitudinal investigation, especially into long-term fertility and live birth outcomes.”
They also emphasize the lack of evidence showing an association between COVID vaccination and fertility outcomes. “The current evidence does not substantiate concerns linking COVID-19 vaccines to impaired fertility or ART failure,” they conclude.