It gets complicated. It has to do with our diets, environment, a steady decline, and sperm count. Let me explain.
On average, men today have a much lower sperm count than men did in the 70s. About 60% less, actually. Published in an article called “Human Reproduction Update,” a doctor says researchers have been looking at all sorts of environmental and chemical factors, and have learned that basically, our “western lifestyle” is what’s causing the most significant decline in our little swimmers.
“Western lifestyle” means, basically, that we use a lot of chemicals (pesticides, cleaners, etc), have more of an unhealthy diet (increased obesity, cholesterol, etc), smoking, high-stress, all these things contribute over time to a decline in men’s sperm count. The study concluded those results in the US, Europe, and Australia. They also found that in South America, Asia, and Africa that there was not as much of a drop, and they actually said “no significant decline” was found, although they do admit there wasn’t as much “data” to analyze. And by “data,” I mean.. Well, you know.
The decline, if it continues, may eventually lead (probably a long time from now) to the eventual extinction of the human species. If you can’t reproduce, well, no more children.