Men diagnosed with infertility are later diagnosed with ischemic heart disease at a higher rate than fertile men. In a 2016 analysis of U.S. insurance claims, Michael Eisenberg and colleagues at Stanford compared men with a fertility diagnosis to men who had undergone vasectomy, a group with proven fertility. The infertile men had a higher incidence of heart disease, diabetes, and several other chronic conditions over the follow-up period (Eisenberg et al., Fertility and Sterility, 2016). The dataset included more than 100,000 men.
That pattern isn't a one-off. So yes, a correlation exists. The harder question is what it means.
The short answer
The correlation is real and appears in multiple large datasets. What those datasets don't show is a simple one-way cause. Male fertility and cardiovascular health share underlying biology, and they share a long list of risk factors. That makes fertility status a useful piece of information about overall health, but it doesn't mean every man with a low sperm count will develop heart disease, and it doesn't mean heart disease causes infertility in every case.
What the observational data shows
The Eisenberg group used insurance claims from a national database to follow men over several years. Men who had been diagnosed with male infertility had more incident heart disease than men who had undergone vasectomy. The comparison matters. Vasectomized men had also seen doctors for reproductive concerns, so the difference was not simply that infertile men were more engaged with the healthcare system. The researchers adjusted for age and existing health conditions, and the association held.
Other research points in the same direction. Semen quality, testicular function, and fertility status have all been linked to later cardiometabolic disease in epidemiological cohorts. The consistency across different countries and study designs is why researchers now describe male infertility as a possible early marker of poor overall health.
Why the two conditions travel together
The simplest explanation is shared risk factors. The same things that damage blood vessels also damage the testicles.
Obesity is one example. Excess visceral fat raises inflammatory markers and insulin resistance. In observational studies, men with higher body mass index tend to have lower sperm concentration and motility. Obesity also drives hypertension, dyslipidemia, and type 2 diabetes.
Type 2 diabetes damages small blood vessels and nerves throughout the body, and several studies have found that men with diabetes have poorer sperm parameters, including higher rates of sperm DNA fragmentation.
Hypertension reflects stiffening of the arterial wall. Some blood pressure medications, particularly older beta blockers and thiazide diuretics, can also affect erectile function and, in some cases, semen quality.
Smoking harms sperm DNA and lowers sperm count in many studies. It also accelerates atherosclerosis.
Anabolic steroid use is a clear case where one behavior affects both systems. Exogenous steroids suppress natural testosterone production and reduce sperm production, while worsening lipid profiles, blood pressure, and cardiac remodeling.
These shared risk factors explain a large portion of the correlation. The biology underneath adds another layer.
The vascular and hormonal overlap
Testosterone sits in both conversations. Men with low testosterone have higher rates of metabolic syndrome and cardiovascular events in some observational cohorts. Testosterone is also required for normal sperm production. The relationship is circular. Low testosterone can be a marker of poor metabolic health rather than a direct cause of heart disease, but the overlap is documented.
Endothelial dysfunction is another common thread. The endothelium is the thin layer of cells lining blood vessels. When it doesn't relax properly, blood pressure rises and atherosclerotic plaque can form. Erectile dysfunction is already recognized as an early warning sign of cardiovascular disease because penile arteries are small and sensitive to endothelial damage. Some researchers think fertility may operate as a similar early signal through the blood supply to the testicles, though that hypothesis is less settled.
Oxidative stress and chronic low-grade inflammation also appear in both conditions. Sperm are sensitive to oxidative damage, and the testicles rely on a dense network of small blood vessels. If those vessels are narrowed or stiff, the environment for sperm production suffers, and the same process may be happening in the coronary arteries.
What this means if you are trying to conceive
A fertility evaluation is a reasonable moment to check cardiovascular risk markers. If you are already seeing a doctor for semen analysis, blood pressure, fasting glucose, and a lipid panel are simple additions. This is especially relevant if you have a family history of early heart disease or have not had bloodwork in the last year or two.
You don't need to panic if your semen parameters come back low. The association is probabilistic. A low sperm count doesn't diagnose heart disease, and a normal sperm count doesn't clear you from cardiovascular risk. The value is in the pattern.
If you have known hypertension, diabetes, or high cholesterol, it is worth discussing with your doctor how those conditions are being managed while you are trying to conceive. Some men find that addressing metabolic health is part of the same conversation as addressing fertility.
Practical levers that address both
Several habits associated with better cardiovascular outcomes are also associated with better sperm parameters in observational studies. These are general health habits, not fertility treatments.
Regular physical activity, including brisk walking, swimming, and lifting weights, is associated with improvements in insulin sensitivity and blood pressure. Observational studies link regular moderate exercise with higher sperm concentration and motility compared with prolonged sitting. You don't need to run marathons. Consistent movement matters more than intensity.
Sleep in the range of seven to eight hours per night is most consistently associated with healthy testosterone levels and cardiovascular function. Short sleep and shift work show up in studies of both poor semen quality and metabolic disease.
Nutrition built around vegetables, fruits, legumes, fish, nuts, and whole grains is associated with lower cardiovascular risk. Several studies also link Mediterranean-style eating patterns with better sperm parameters. Limit sugary drinks, processed meats, and deep-fried foods.
Tobacco and alcohol deserve separate attention. Quitting smoking is one of the strongest things a man can do for both blood vessels and sperm DNA. Heavy alcohol use is associated with lower testosterone, poorer semen quality, and higher blood pressure.
Weight management works through insulin sensitivity and blood pressure. Losing even a small amount of weight, around 5 to 10 percent of body weight, is associated with improvements in blood pressure and insulin sensitivity in people with overweight. Some studies report parallel improvements in sperm parameters, though the response is not universal.
These are levers, not guarantees. The same daily choices move both health domains in the same direction.
What the research cannot tell you yet
All of this comes from observational data, so the word is correlation, not causation. Men with undiagnosed cardiovascular disease may be less likely to conceive for reasons unrelated to sperm quality, such as reduced libido or erectile function. The association could also work through reverse causation. A man who has a heart condition may have less frequent intercourse or lower sexual function, which leads to a fertility evaluation and a label of infertility.
The Eisenberg study's use of vasectomized men as a control reduces some of that bias, but no observational design can remove it entirely. A randomized trial can't answer this question directly. You cannot assign men to have poor fertility and then wait to see who develops heart disease. The evidence is consistent enough to take seriously, but it isn't settled at the level of individual prediction.
Men with fertility concerns should not assume they have heart disease. Men with heart disease risk factors should not assume they are infertile. The research supports a shared foundation, not a one-to-one link.
This content is for educational purposes only and is not medical advice. Oakman products are designed for physical comfort and cooling. They make no claims about fertility, sperm quality, or hormone levels. Consult a healthcare professional for personalized advice.