As Sperm Count declines

As Sperm Count declines

Researchers have published data showing the quality of sperm counts in men had been cut nearly in half over the previous 50 years. According to this study:

As male fertility is to some extent correlated with sperm count the results may reflect an overall reduction in male fertility. The biological significance of these changes is emphasized by a concomitant increase in the incidence of genitourinary abnormalities such as testicular cancer and possibly also cryptorchidism and hypospadias, suggesting a growing impact of factors with serious effects on male gonadal function.”

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Are Humans Going Extinct?

Shanna Swan, Ph.D., a leading environmental and reproductive epidemiologist and professor of environmental medicine and public health at the Icahn school of Medicine at Mount Sinai in New York City, was initially skeptical, but she decided to look into it some more. To her amazement, after reviewing each of the 60 studies included in that 1992 analysis, she could find nothing to indicate that the finding was a fluke. It was the most stable trend she’d ever come across, and she spent the next 20 years investigating why human reproduction is plummeting.

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In 2017, she published a systematic review and meta-regression analysis2 showing a 50% to 60% drop in total sperm count among men in North America, Europe, Australia and New Zealand between 1973 and 2011. Overall, men in these countries had a 52.4% decline in sperm concentration and a 59.3% decline in total sperm count (sperm concentration multiplied by the total volume of an ejaculate).

Swan refers to this shocking 39-year decline as “the 1% effect,” meaning the cumulative effect that an annual change of just 1% has over time. Testosterone has also declined in tandem with lower sperm counts, while miscarriage rates among women and erectile dysfunction among men have been steadily rising.

If these trends continue, and there’s no indication that they won’t, in the not-so-distant future, we’ll be looking at a male population that is completely infertile. At that point, the human population will become extinct. Along the way, however, we’ll be facing a number of other pressing problems.

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How Will We Care for Aging Baby Boomers?

Historically, the age distribution of the population has looked like a pyramid. The bottom largest section was children, the middle, slightly smaller section was working adults, and the top of the pyramid was seniors. This worked out well, because the younger population was able to financially support and care for the much smaller older segment.

We no longer have that pyramid. In most countries, the population distribution now looks like a light bulb, with a narrow base of children, a bulbous segment of adults, and a narrowing but still very large segment of older adults.

Part of the equation is the fact that life spans have gotten longer, which is wonderful. But the funds to support this aging population — through social security and Medicare in the U.S., for example — are dwindling, as the payer base is shrinking so dramatically.

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Another problem is the fact that we won’t have the labor force required to keep the economy afloat. There aren’t enough children to fill all the jobs after the adult population retires.

What’s the Cause?

According to Swan, there are likely a whole host of factors contributing to this reproductive calamity. We can, however, rule out genetics, because the decline in sperm count is simply too rapid. A 50% decline in just two generations cannot be explained by genetics.

That leaves us with environmental causes. Environmental causes can be broadly divided into two broad categories: Lifestyle and chemicals. Lifestyle factors that negatively impact fertility include:

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  • Obesity
  • Smoking
  • Binge drinking
  • Stress

On the chemical side, we know that a great number of chemicals can impact fertility either directly or indirectly, but the most concerning class are endocrine disrupting chemicals (EDCs). EDCs disrupt hormones, including sex hormones necessary for reproductive function.

Many EDCs will mimic hormones, effectively taking their place. But, of course, the chemical doesn’t function the way the natural hormone does, so whatever that hormone controls won’t function well either. As explained in the 2019 report, “Male Infertility and Environmental Factors”:

“Classically the EDCs bind to the androgen or estrogen receptor triggering an agonist or antagonist action. These in turn lead to increased or decreased gene expression of sex-specific genes.

In addition, EDCs act on steroidogenic enzymes and the metabolism of hormones, for example, inhibit the activity of 5-α reductase, which is the most important enzyme in the production of dihydrotestosterone and hence the regulation of the masculinization of the external genitalia and the prostate.

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Furthermore, P450 enzymes in the liver that metabolize steroid hormones may be affected. In animal models EDCs affect hormone receptor levels. In addition to the effect on hormone action, animal experiments suggest that EDCs may also result in epigenetic changes and miRNA levels.”

Shaw suspects EDCs are a primary culprit in infertility, in part because we’re surrounded by them every day of our lives. We’re exposed to them through our food, water, personal care products, furniture, building materials, plastics and much more.

In Utero Exposure to EDCs Can Drive Down Fertility

The most vulnerable time of a person’s life is in utero. This is when the building blocks for your reproductive system are laid down, and exposure to EDCs at this time can wreak havoc with a child’s adult reproductive capacity. Since the fetus shares the mother’s body, everything the mother is exposed to, the fetus is exposed to.

A boy’s reproductive system is dependent on a certain level of testosterone for proper development. If the testosterone level is too low, his reproductive system will be impaired to some degree. In short, without sufficient testosterone, the boy’s reproductive system will “default” to female. He will be feminized, or as Shaw describes it, “incompletely masculinized.”

Phthalates Are in Everybody

Shaw was tipped off to investigate phthalates by a chemist at the U.S. Centers for Disease Control and Prevention, who noted that these EDCs have been found in everybody, including pregnant women.

Specifically, phthalates have been shown to disrupt the reproductive development of males, because they lower testosterone levels and incomplete male development in animals has now become so prevalent, there’s even a name for it: phthalate syndrome.

Animal studies have shown that when a pregnant mother is fed phthalates in early pregnancy, her male offspring will have smaller and less developed reproductive organs. His testicles may not be descended, his penis may be smaller, and his anogenital distance (the distance between the anus and the genitals) tends to be shorter.

Shaw was the first to study the anogenital distance in human male infants, and was able to confirm phthalate syndrome is occurring in humans as well. Boys born of women with high levels of phthalic metabolites in their urine — specifically those that lower testosterone — had phthalate syndrome, and the severity was dose-dependent.

Shaw then replicated the study with another set of mothers and their babies, and found the same result. The next question then is, does a shorter anogenital distance result in lower sperm count?

According to Shaw, boys with a short anogenital distance are more likely to have reproductive defects such as undescended testicles and defects of the penis. He’s also more likely to develop testicular cancer at an earlier age than normal, and he’s more likely to be sub-fertile.

So, it is her professional conclusion that phthalate exposure in utero is “undoubtedly part of the explanation of the decrease in sperm count and fertility.” Phthalates and polyfluoroalkyl substances (PFAS) have also been linked to reduced bone mineral density in male teens,5 which could have significant implications later in life.

Common Sources of Phthalate Exposure

Phthalates are found in plastics. They’re what make the plastic soft and flexible, so wherever you find soft and pliable plastic, you find phthalates. Examples include:

  • Vinyl clothing, such as raincoats and rubber boots
  • Plastic shower curtains
  • Plastic tubing of all kinds
  • Foods that have been processed through plastic tubing, such as dairy products (the milking machines have plastic tubing)

Phthalates also increase absorption and help retain scent and color, so you’ll find them in:

  • Cosmetics, perfumes and personal care products
  • Scented household products such as laundry soap and air fresheners
  • Pesticides

As noted by Shaw, phthalates are only one class of EDCs. There are several others, including phytoestrogens, dioxins, flame retardants, phenols, PCBs and polyaromatic hydrocarbons. Phthalates, however, are among the most hazardous for male reproductive health due to their ability to block testosterone. (SPOTIFY)

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