COVID-19 does reduce testosterone levels in men, sometimes sharply. During acute infection, studies have documented drops of roughly 30% or more from pre-illness baselines, with the lowest levels appearing in the sickest patients. The good news is that testosterone generally rebounds during recovery, but the rebound is not always complete, and a meaningful fraction of men still show low levels months after the virus has cleared. The relationship between the virus and male hormones turns out to be a two-way street, with testosterone influencing how severe the disease becomes and the disease in turn suppressing testosterone production through several distinct pathways.
How Much Does Testosterone Drop During Acute Infection?
One of the clearest early snapshots came from a cohort of men who happened to have recent testosterone tests on file before they got sick. Their average total testosterone fell from about 458 ng/dL before COVID-19 to around 315 ng/dL during active infection, a decline of roughly a third.1PubMed. Effect of serum total testosterone and its relationship with other laboratory parameters on the prognosis of coronavirus disease 2019 (COVID-19) in SARS-CoV-2 infected male patients: a cohort study That kind of drop is large enough to push many men below the clinical threshold for low testosterone, which most labs set somewhere around 300 ng/dL. A Hamburg ICU study found that roughly 69% of male COVID-19 patients admitted to intensive care had low testosterone on arrival, and that those low levels tracked closely with markers of inflammation.2medRxiv. The majority of male patients with COVID-19 present low testosterone levels on admission to Intensive Care in Hamburg, Germany: a retrospective cohort study
The severity of the testosterone drop scales with the severity of the illness. Researchers who grouped patients by disease severity found that men with mild COVID-19 had average testosterone around 2.19 ng/mL, those with moderate illness averaged about 1.29 ng/mL, and those with severe disease averaged just 0.75 ng/mL.3PubMed Central. Serum Testosterone Is Associated With the Severity of COVID-19 Lower testosterone was also independently linked to a higher risk of ICU admission and death, even after accounting for other clinical variables.4PubMed Central. Severely low testosterone in males with COVID-19: A case-control study
Why the Virus Hits Testosterone Production
The testes are not just collateral damage. SARS-CoV-2 gets into human cells by latching onto a receptor called ACE2, and gene-expression mapping of testicular tissue has shown that ACE2 is concentrated in exactly the cells responsible for making testosterone: Leydig cells, Sertoli cells, and spermatogonia. A companion protein the virus uses for entry, TMPRSS2, is also present in spermatogonia and spermatids.5PubMed Central. scRNA-seq Profiling of Human Testes Reveals the Presence of the ACE2 Receptor, A Target for SARS-CoV-2 Infection in Spermatogonia, Leydig and Sertoli Cells In other words, the testes have the biological welcome mat the virus needs to walk in.
Autopsy studies of men who died from COVID-19 confirmed the damage. One study found that the average number of Leydig cells in COVID-19 testes was dramatically lower than in controls (about 2.2 versus 7.8), along with swelling and immune-cell infiltration in the tissue between the tubules.6PubMed Central. Pathological Findings in the Testes of COVID-19 Patients: Clinical Implications Another autopsy series found mild orchitis (testicular inflammation) in the majority of cases, along with blood clots in small vessels, reduced numbers of both Leydig and Sertoli cells, and decreased sperm production.7PubMed Central. Testicular pathology in fatal COVID-19: A descriptive autopsy study These findings come from fatal cases, so they represent the extreme end, but they illustrate the mechanisms at play: direct viral invasion of testosterone-producing cells, inflammatory damage, and impaired blood flow.
The virus does not need to reach the testes directly to suppress testosterone, though. The body’s inflammatory response alone can do significant harm. In critically ill men, testosterone levels correlated inversely with inflammatory signaling molecules: as inflammatory markers went up, testosterone went down.2medRxiv. The majority of male patients with COVID-19 present low testosterone levels on admission to Intensive Care in Hamburg, Germany: a retrospective cohort study This is actually a well-known pattern: any severe illness with a strong inflammatory component tends to suppress the hypothalamic-pituitary-gonadal axis, the hormonal chain of command that tells the testes to produce testosterone. COVID-19 appears to hit this system especially hard.
The Hormonal Chain of Command Gets Disrupted
What makes the testosterone suppression in COVID-19 particularly interesting is where the problem sits in the hormonal hierarchy. When testosterone drops because the testes are damaged, the brain normally responds by ramping up a signaling hormone called LH to try to compensate. But a study of 60 ICU patients found that almost all of them had low testosterone, and the vast majority did not show the expected compensatory rise in LH. Out of 57 patients with low testosterone, only 6 showed the LH spike you would expect from straightforward testicular damage. Thirteen had very low LH, and 38 had levels that were not clearly elevated.8The Lancet (eBioMedicine). Hypothalamic and gonadal involvement in COVID-19 patients This pattern points to a problem upstream, in the hypothalamus or pituitary gland, not just in the testes themselves.
A cross-sectional study from southern Iran put numbers on this, finding that among men with severe or critical COVID-19, about 75% had signs of secondary hypogonadism (meaning the brain was not sending the right signals to the testes) and about 20% had primary hypogonadism (meaning the testes themselves were failing). Combined, over 95% of the severely ill men in that cohort met criteria for some form of hypogonadism.9PubMed Central. Impact of COVID-19 on pituitary function: a cross-sectional study in southern Iran These numbers are striking, though they come from the sickest patients and should not be extrapolated to everyone who catches COVID-19.
Does Testosterone Recover After the Infection Clears?
For most men, the answer is yes, but the timeline varies and recovery is not always complete. A 12-month follow-up study that tracked men from their acute hospitalization found that median testosterone climbed substantially from baseline through follow-up visits, rising from very low levels during illness to values in the normal range by about seven months. Both the inflammatory markers and the abnormally elevated estradiol levels that accompanied acute illness also came down over time.10PubMed Central. Testosterone in males with COVID-19: a 12-month cohort study
The catch is that “most men recover” and “all men recover fully” are not the same statement. A separate prospective study noted that while testosterone levels improved over time after COVID-19, a significant proportion of men still had low levels at 12-month follow-up.11PubMed. Male Hypogonadism After Recovery from Acute COVID-19 Infection: A Prospective Observational Study At the six-month mark in another cohort, nearly half the men tested still had low testosterone.12PubMed. The association of free testosterone levels with coronavirus disease 2019 And the ICU study mentioned earlier found that when patients were rechecked at a median of about seven months after their initial presentation, roughly 23% of the men still had low testosterone without the expected compensatory LH rise, suggesting ongoing disruption of the hormonal axis.8The Lancet (eBioMedicine). Hypothalamic and gonadal involvement in COVID-19 patients
Animal data tells a similar story. In a mouse model engineered to be susceptible to SARS-CoV-2, testosterone declined significantly during the early recovery period and, while it crept upward over the following weeks, it remained lower than control levels a month after infection. The mice also showed reduced sperm counts and disrupted steroidogenic pathways in testicular tissue.13PLoS Pathogens. SARS-CoV-2-induced cytokine storm drives prolonged testicular injury and functional impairment in mice that are mitigated by dexamethasone
Fertility and Sperm Quality
The testosterone story is only part of the fertility picture. Because the virus targets the same testicular cells involved in sperm production, COVID-19 can impair semen quality directly. Men who had recently recovered from either mild or severe infection showed lower semen volume, lower total sperm counts, reduced motility, and decreased viability compared to healthy controls, with these effects persisting for at least three months after diagnosis.14PubMed Central. COVID-19 associates with semen inflammation and sperm quality impairment that reverses in the short term after disease recovery The researchers in that study also documented elevated inflammatory markers in the semen itself, suggesting that local inflammation, not just systemic illness, was contributing to the damage.
For couples trying to conceive, the practical takeaway is that a period of reduced fertility after COVID-19 is plausible but likely temporary. A full cycle of sperm production takes roughly 70 to 90 days, so even temporary testicular insults need several months to fully wash out. Men who had moderate to severe COVID-19 and are struggling with fertility afterward may benefit from having their hormone levels and semen parameters checked, particularly if they are not seeing improvement after four to six months.
Sexual Health and Erectile Dysfunction
Low testosterone is one contributor to erectile dysfunction, and post-COVID men appear to face elevated risk. A study of long-COVID patients with erectile dysfunction found that their total testosterone, free testosterone, and free androgen index were all significantly lower than in controls without long COVID. These men also reported worse erectile function on standardized questionnaires.15Scientific Reports. Long COVID and risk of erectile dysfunction in recovered patients from mild to moderate COVID-19 A Mendelian randomization study, which uses genetic variation to probe cause-and-effect relationships, found evidence consistent with a causal link between COVID-19 infection, reduced testosterone, and increased erectile dysfunction risk.16PubMed Central. COVID-19 infection may reduce serum testosterone levels and increase the risk of erectile dysfunction: A two-sample Mendelian randomization study
Testosterone is not the only piece of this puzzle, though. COVID-19 also damages blood vessels, impairs endothelial function, and can cause psychological effects like anxiety and depression, all of which independently contribute to erectile problems. Men who notice new sexual difficulties after COVID-19 should not assume their testosterone is the sole culprit, but getting it checked is a reasonable first step.
The Age Factor and Why Older Men May Be More Vulnerable
Testosterone levels decline naturally with age, which means many older men start from a lower hormonal baseline before they ever encounter the virus. This matters because the immunosuppressive effects of low testosterone may compound the vulnerability that aging already creates. The connection between low testosterone, heightened inflammatory markers like IL-6, and the development of acute respiratory distress syndrome has been raised as one explanation for why elderly men have higher COVID-19 mortality than elderly women.17Wiley Online Library (Andrology). Why does COVID-19 kill more elderly men than women? Is there a role for testosterone? The idea is not that testosterone protects against the virus per se, but that men who already have low levels may lack the hormonal environment needed to keep inflammation in check once infection takes hold.
Obesity, type 2 diabetes, and metabolic syndrome, all of which are independently associated with lower testosterone, are also major risk factors for severe COVID-19. Untangling how much of the testosterone-severity link reflects direct hormonal effects versus shared underlying metabolic dysfunction remains an open question. But for men who already know their testosterone is low, it is worth flagging with a physician in the context of COVID-19 risk.
COVID-19 and Testosterone in Women
The testosterone conversation is overwhelmingly focused on men, but women also produce small amounts of testosterone, and COVID-19 interacts with their androgen levels in different and somewhat paradoxical ways. In hospitalized women, higher testosterone has been associated with worse inflammatory profiles, essentially mirroring elevated inflammation rather than indicating a protective hormonal reserve.18PubMed Central. Serum testosterone mirrors inflammation parameters in females hospitalized with COVID-19
Women with polycystic ovary syndrome (PCOS), who often have elevated androgen levels, appear to face higher susceptibility to SARS-CoV-2 infection and may be more likely to develop symptoms. The excess androgens characteristic of PCOS may upregulate the TMPRSS2 protein that helps the virus enter cells, and the metabolic dysfunction that accompanies the condition, including insulin resistance and central obesity, adds additional risk.19PubMed Central. Polycystic ovary syndrome and risks for COVID-19 infection: A comprehensive review So while low testosterone in men is linked to worse outcomes, higher androgens in women with PCOS may also signal trouble, likely because of the underlying metabolic picture rather than the testosterone itself.
Is Testosterone Replacement Therapy Safe During the Pandemic?
Men who were already on testosterone replacement therapy (TRT) when the pandemic began faced an uncomfortable question: could supplemental testosterone make COVID-19 worse, perhaps by boosting TMPRSS2 expression and giving the virus an easier way in? The androgen receptor is a known driver of TMPRSS2 production, particularly in the prostate.20Nature Communications. The antiandrogen enzalutamide downregulates TMPRSS2 and reduces cellular entry of SARS-CoV-2 in human lung cells This led to early speculation that men on TRT might be at higher risk.
The data so far is reassuring. A large randomized trial found that the incidence of COVID-19 was essentially the same in men on TRT as in those on placebo, with about 8% in each group contracting the disease over three years. Hospitalization and death rates also did not differ significantly between groups.21PubMed Central. Testosterone Replacement Therapy and Risk of COVID-19 and Effect of COVID-19 on Testosterone’s Treatment Effect An earlier observational study similarly found that men on TRT who were diagnosed with COVID-19 had comparable rates of hospitalization, blood clots, ICU admission, and death as infected men not on TRT.22The Journal of Sexual Medicine. COVID-19 Infection in Men on Testosterone Replacement Therapy Men on TRT do not appear to need to discontinue therapy out of concern for COVID-19, though this is a conversation to have with a prescribing physician based on individual risk factors.
Vaccines and Male Hormones
A separate and persistent worry has been whether COVID-19 vaccines themselves affect testosterone or male fertility. The evidence here is clear: they do not, in any clinically meaningful way. A systematic review and meta-analysis of studies across mRNA, viral-vector, and inactivated vaccines concluded that COVID-19 vaccination had no harmful effect on semen quality.23PubMed Central. Effect of COVID-19 vaccination on semen parameters: A systematic review and meta-analysis A broader post-pandemic literature review reached the same conclusion: while men may see minor, short-lived fluctuations in semen parameters after vaccination, these stay within normal physiological ranges and do not affect the likelihood of achieving pregnancy.24PubMed Central. Effects of COVID-19 vaccination on human fertility: a post-pandemic literature review
This distinction matters. The virus itself poses a demonstrable, sometimes prolonged threat to testosterone levels and reproductive function. The vaccines do not. For men concerned about preserving their hormonal health, vaccination represents protection from the hormonal disruption caused by the disease, not a risk to it.
When to Get Your Levels Checked
If you had a moderate to severe bout of COVID-19 and are experiencing symptoms consistent with low testosterone, such as persistent fatigue, low libido, difficulty concentrating, mood changes, or erectile dysfunction, it is reasonable to have your testosterone tested. Timing matters: checking during or immediately after acute illness will almost certainly show suppressed levels, and those readings reflect the inflammatory state rather than your baseline hormonal health. A more informative test comes at least three months after recovery, with a recheck at six to twelve months if the initial value is low.
Symptoms of low testosterone overlap substantially with long-COVID symptoms more broadly, including brain fog, fatigue, and mood disturbance. This overlap means that low testosterone could be contributing to some of what gets labeled as long COVID in men, but it also means that attributing all post-COVID symptoms to hormones would be a mistake. A blood test is the only way to know, and if levels are genuinely low and not recovering, there are well-established treatment options your doctor can discuss.
For men whose testosterone was already on the lower end before infection, tracking recovery more closely makes sense. The data suggests that most men’s levels will normalize within several months, but about one in four or five may still be below normal at the six-to-twelve-month mark. Those men deserve evaluation rather than reassurance that it will sort itself out eventually.