A new study, whose results are being presented at the Endocrine Society’s 100th annual meeting in Chicago this week, has made an association between lower sperm count and other health afflictions, including lower bone mass, increased cardiovascular risk, and alterations to metabolism. In general, it seems that a man’s sperm count is a marker of his overall health.
Before we take a look at the study itself, some important caveats. Firstly, this research definitely doesn’t demonstrate a cause-and-effect relationship between sperm count and other medical conditions. These associations are correlations only, and it’s likely that a lower sperm count is also a feature of an underlying health problem that causes other effects.
The study is the most extensive of its kind, having examined 5,177 male partners of infertile couples, but all were from Italy, and it’s not clear if the same association can be found across a range of demographics or men from a variety of ethnic backgrounds.
The research is yet to be peer-reviewed at the time of writing, so certain details remain elusive. If corroborated with additional research, however, then the implications of the study are clear: Fertility levels in men may sometimes be a proxy for their general health.
So what exactly did the team – led by the Universities of Brescia and Padova – find?
Of those examined during the research, half the men had low sperm counts, less than 39 million spermatozoa per ejaculate. They were 20 percent more likely than those with normal sperm counts to have greater body fat, higher blood pressure, more low-density lipoprotein (LDL, the “bad” cholesterol) and triglycerides (another type of blood-borne fat), and less high-density lipoprotein (HDL, the “good” cholesterol).
As noted by a press release, they were also at a higher risk of “metabolic syndrome”, which refers to a combination of diabetes, high blood pressure, and obesity. This makes stroke, coronary heart disease, and related conditions more likely later in life.
Speaking of diabetes, those with low sperm counts were also more likely to show indications of insulin resistance, a “precursor” to said affliction. They were also at a far higher risk of having low testosterone levels; half of these low-testosterone men were also more likely to have lower bone mass, which makes bones more vulnerable to breaks.
All in all, a lower sperm count sounds like it’s a mirror of plenty of rather worrisome conditions, but remember, having a low sperm count doesn’t automatically mean you have all, or some, of these other health problems. This study merely suggests that if you’re found to have lower fertility levels, you should be given a more in-depth health check.
Something else worth emphasizing is that we don’t know any values of absolute risk yet. How likely is a low sperm count male to get coronary heart disease in his lifetime compared to a normal sperm count male, for example, assuming no other factors are at play? Details like this will probably have to wait until the study itself is published.
Since 1973, there has been a 50-60 percent drop in sperm count in Western nations (and only Western nations so far), although no-one’s quite sure what’s causing it. If this new study’s associations hold up, then one could posit that this lowering sperm count may be related to a decline in general male health over the past few decades.