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What Are the Causes of Infertility in Men?


Officially, infertility is defined as the inability of a couple to conceive a child after one year of unprotected sex. Traditionally (and unfairly), infertility has most ofter been blamed on or attributed to women. However, stats show that in most cases infertility is evenly attributable to both men and women; with about 40% of cases being attributed to men and 40% being attributed to women. The remaining 20% of infertility cases are either attributable to both men and women simultaneously or they have an unknown cause.

In men, the causes of infertility are many and varied. They include a number of well-documented genetic, environmental and lifestyle factors such as:

  • Infections
  • Tumors
  • Side Effects of Medications
  • Exposure to Radiation
  • Exposure to certain Industrial Chemicals
  • Smoking and Using Illicit Drugs
  • Obesity
  • Alcohol
  • Heavy Drug and Tobacco Use

However, there are also a few suspected (unproven) causes of infertility that many experts feel are worth looking into. These are listed below:

  • BPA
  • Gluten Sensitivity
  • Soy-Based Products
  • Electromagnetic Waves

Known Causes (In Detail)



Bacterial infections can damage (sometimes irreversibly) any portion of the male reproductive tract. Genital tract infections (either acute or chronic) are particularly harmful to a man's fertility. These infections range from gonorrhea, mumps and tuberculosis to chlamydiae, syphilis, and pancreatitis.

Surprisingly, one of the ways that these bacterial infections cause infertility in men is by turning men's immune systems against their own spermatozoa. Usually, the male genital tract is a closed tube and so spermatozoa are isolated from the body's immune system. However, bacterial infections can weaken this natural barrier between spermatozoa and the immune system. Once the immune systems detects spermatozoa, it can then build antibodies against them; causing real problems for male fertility.


The presence of tumors both on the testicle and on other important organs such as the pituitary gland can affect sperm production and therefore, contribute to male infertility. Moreover, the treatment for these very same tumors worsen male infertility issues.

For instance testicular tumors, whether cancerous or not, can negatively affect sperm production and motility. Yet, even the treatment for testicular cancer



There are various classes of drugs that can cause infertility in men. These medications operate through various mechanisms in the body and the degree and severity of infertility will vary from medication-to-medication, person-to-person. Luckily, for many of these medications, infertility will cease once an individual has been taken off the drug or receives some counteractive treatment. A small sampling of the classes of drugs that can infertility and impotence are listed below with their corresponding descriptions:

  1. Testosterone: As a general rule, men who take supplemental testosterone experience a sharp drop in semen production. An excess of testosterone in the bloodstream will not only only decrease (natural) testosterone production in the testes but also block the hormonal signals that tell the testes to make semen.
  2. Opiates: Extended use of opiates (prescription or street dealt) can disrupt that signals that tell the testes to produce semen. This could lead to a decrease in overall semen production or negatively affect semen quality.
  3. 5-alpha-reductase inhibitors: These clases of drugs are used treat both prostate enlargement and hair loss. While those using them to treat prostate enlargement generally experience more negative effects on their fertility; side effects generally stop once the patient ceases treatment.
  4. Selective serotonin reuptake inhibitors (SSRIs): These classes of drugs are used to anxiety and depression. However, these drugs also seem to affect the otherwise proper movement of sperm through the reproductive tract.


Radiation as a cause of infertility in men has been studied at length; and the most useful results have come to us from the field of cancer treatment. As a general rule of thumb, radiation is very damaging to sperm cells and their composite parts. The severity of damage that can occur to testes and and sperm after direction radiation exposure vary with the dose of radiation, the amount of sheilding involved and how many exposures occured within a given time frame.

As a side note testicular exposure to radiation is only one way in which radiation can cause infertility in men. In some brain surguries, radiation therapy has been applied to the brain. If radiation damages vital brain areas such as the pituitary gland, semen and testosterone production are likely consequences.

heavy alcohol and/Or tobacco use:

In a similar way to the medications that were described above, heavy use of alcohol and tobacco can disrupt that natural hormonal signals that tell your body to produce (healthy) sperm and semen. This of course should make sense as both alcohol and tobacco are technically drugs. Heavy consumption of either can result in less sperm production, lower quality sperm and even erectile dysfunction.



Studies conducted at the National Institute of Environmental Health Sciences (NIEHS) have found that men with higher Body Mass Indices (BMI's) are more likely to experience infertility as well as a host of other reproductive health issues. Other (similar) studies have found for every 20 pounds a man gains above his normal BMI, the decrease in his fertility can be as high 10%.

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Obesity directly affects fertility because a man with excess amounts of fat in his system will inadvertently convert a substantial amount of his body's testosterone into estrogen. This may cause a lowering of natural testosterone in the testes, which will lower sperm counts. Preliminary studies have shown that obese men can have estrogen levels that are 20% higher than men of normal weight.

Exposure to industrial chemical:

Certain industrial chemicals have been implicated in disrupting the endocrine and reproductive systems of both men and women. Over time it is suspected that these synthetic chemicals can temporarily or even permanently cause infertility in men. A small list of suspected industrial chemicals are as follows:

  1. Nonylphenol ethoxylates (NPEs): Used in detergents, paints, pesticides and plastics; this class of chemicals not only act as endocrine disruptors in the human but also change gene expression. They are also generally known to mimic estrogen in the human body.
  2. Perfluorooctanoic acid (PFOA): Is a common ingredient in grease and stain resistant coatings and additives such as Teflon and Gore-Tex. However, it has been identified as a likely carcinogen.
  3. Monosodium Glutamate (MSG): A notorious food additive that is ubiquitous in potato chips, soups, and a variety of asian foods; has also been implicated in changing gene expression and the function of reproduction organs. Studies done on laboratory mice have shown that MSG may decrease reproductive success by as much as 50% across generations.
  4. Trichloroethylene (TCE): Although its usage has decreased greatly in recent years, trichloroethylene was for many years used as an industrial solvent. Over the course of many years, studies revealed its deleterious effects on both male and female reproductive cells.

Suspected Causes (In Detail)


(bisphenol A) BPA:

An endocrine disruptor that can be found in an extremely wide variety of plastics, can liners and receipts. In the past few years, researchers have identified it as one of the chief chemical instigators that may have contributed to the decline in male infertility over the past few decades. (More on this later int he article). Other studies have observed a direct correlation between high levels of BPA in men's urine and low sperm counts in men.

In the body, BPA mimics estrogen. And as we mentioned before, this can detrimental to men's sexual health and development because the body needs a certain level of testosterone in its system to maintain healthy semen production.

Gluten Sensitivity:

As you may or may not know, infertility is one of the possible symptoms of celiac disease in both men and women. Men with celiac disease are reported to have abnormal sperm sizes and shapes. However, it is suspected that men with "gluten sensitivity" are indirectly causing or at least worsening their infertility condition.

Soy-Based Products:

Although there are no long-term conclusive studies that link fertility to soy consumption; there are many reasons to suspect that soy could be a major contributor to the generational fertility problems present in men (especially in the developed world).

It is widely known that soy mimics estrogen in the body, and as we explained in previous sections, excessive amounts of estrogen in the system can negatively affect sperm count and quality. However, the chief concern stems from the fact that soy is in everything. Soy is even in a certain percentage of baby formulas that are currently on the market.

Cellphone Radiation:

There has been controversy about this subject ever since 2005. but the concern may be warranted. A series of studies and follow-up studies have confirmed that cell phone radiation does sperm motility and it introduces more free radicals into semen than would otherwise be there. However, there does not appear to be any damage to the genetic material that semen contains from exposure to cell phone radiation.

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The Global Fertility Problem:


Across almost all demographics in all the developed nations; male fertility has been in decline for the past quarter century. Over this same time frame, the average sperm count for the typical (child-bearing age) male has decline by 25%. Moreover, this decline in sperm counts has been accompanied by an even more disturbing rise in testicular cancer rates.

All of this begs the question: What is the cause of this widespread fall in sperm counts? So far, there are no clear answers; and there may be no clear answer for years to come. However, preliminary analysis suggests that the cause is probably environmental in nature.


Gary on August 06, 2017:

Great information. Thanks for sharing it.

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