In 1992, researchers published data showing the quality of sperm counts
in men had been cut nearly in half over the previous 50 years. A 2017
systematic review confirmed this trend, showing a 50% to 60% drop in
total sperm count among men in North America, Europe, Australia and New
Zealand between 1973 and 2011.
Testosterone has also declined in
tandem with lower sperm counts, while miscarriage rates among women and
erectile dysfunction among men have been steadily rising.
We
can rule out genetics as the cause because the decline in sperm count is
simply too rapid. That leaves us with environmental causes that can be
broadly divided into two categories: lifestyle and chemicals.
In
1992, researchers 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:1
“Linear regression of data weighted by number of
men in each study showed a significant decrease in mean sperm count from
113 x 10(6)/ml in 1940 to 66 x 10(6)/ml in 1990 and in seminal volume
from 3.40 ml to 2.75 ml, indicating an even more pronounced decrease in
sperm production than expressed by the decline in sperm density …
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.”
Swan 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.
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 problem...<<<Read More>>>...
