Human fertility is in a downward spiral, scientists warn and modern life — with its technological and chemical “progress” — is likely to blame. Female infertility tends to get the most attention, but in this case, it’s male infertility that has made headlines, as recent research shows sperm concentration and quality has dramatically declined in recent decades.1,2,3,4,5
According to the first of two recently published papers,6 a meta-analysis of 185 studies and the largest of its kind, sperm counts around the world declined by more than 50 percent, to 47 million sperm per milliliter (mL), between 1973 and 2013, and continue to dwindle.
The most significant declines were found in samples from men in North America, Europe, Australia and New Zealand, where many had sperm concentrations below 40 million/mL. (Men suspected of infertility, such as those attending IVF clinics, were excluded from the study.) Overall, men in these countries had a 52.4 percent decline in sperm concentration and a 59.3 percent decline in total sperm count (sperm concentration multiplied by the total volume of an ejaculate).
Male Infertility Rates Warn of Impending Human Extinction
According to the World Health Organization, 40 million sperm per mL is considered the cutoff point at which a man will have trouble fertilizing an egg, which means half of the men in most developed nations are near or at the point of being infertile. South American, Asian and African men had no noticeable decline, although this discrepancy could be due to the smaller sample sizes obtained from those countries.
As noted by Frederick vom Saal, professor emeritus of biological sciences at the University of Missouri, who was not involved in the study, these findings are a wake-up call and a warning that “we are in a death spiral of infertility in men.” Indeed, lead author Dr. Hagai Levine, who called the results “profound” and “shocking,”7 worries that human extinction is a very real possibility, should the trend continue unabated.8
Danish researcher and pediatrician Dr. Niels Skakkebæk, who in 1992 published a paper9 showing male fertility declined between 1940 and 1990, also commented on the findings, saying:
"These two new papers add significantly to existing literature on adverse trends in male reproductive health problems … Here in Denmark, there is an epidemic of infertility. More than 20 percent of Danish men do not father children. Most worryingly [in Denmark] is that semen quality is in general so poor that an average young Danish man has much fewer sperm than men had a couple of generations ago, and more than 90 percent of their sperm are abnormal."
Endocrine Disrupting Chemicals Wreak Havoc on Men’s Reproductive Ability
The second paper,10 published in PLOS Genetics, suggests endocrine disrupting chemicals are to blame for the dramatic decline in reproductive health among men.11 It found that exposing male mice to ethinyl estradiol, a synthetic sex hormone found in birth control pills, causes developmental problems in the reproductive tract, thereby lowering sperm counts.
While men do not use birth control pills, they’re exposed to them nonetheless through contaminated water and other sources. Men are also exposed to a number of other endocrine disrupting chemicals in their day-to-day lives,12 thanks to the pernicious use of endocrine disrupting chemicals in plastics, personal care products, herbicides such as glyphosate13 (which is a very common contaminant in non-organic foods) and more.
The study also confirmed that the effects of environmental estrogens have generational effects. Males are successively becoming increasingly more sterile with each passing generation. As reported by Environmental Health News:14
“They observed adverse effects starting in the first generation of mouse lineages where each generation was exposed for a brief period shortly after birth. The impacts worsened in the second generation compared to the first, and by the third generation the scientists were finding animals that could not produce sperm at all.
This latter condition was not seen in the first two generations exposed. Details of the experimental results actually suggested that multiple generations of exposure may have increased male sensitivity to the chemical.”
Testicular cancer is also on the rise, as are congenital malformations of the penis, and these problems have also been linked to endocrine disrupting chemicals. Experiments on fathead minnows show endocrine disrupters turn the fish into a sterile intersex species, meaning they have both male and female reproductive systems yet are incapable of reproducing.15
While women are also adversely affected by these kinds of chemicals, men are disproportionally affected due to the way the male reproductive system develops in utero. At the outset, male and female fetuses are fairly identical. Sex hormones are what drive the differentiation between the sexes. Alas, when synthetic chemicals that mimic these all-important hormones enter into the mix, it confuses the process and interferes with the biological process of turning the fetus into a male.