Sperm count down date:
Yeah. Right. It’s an update. But one tries to be clever.
There has been another assessment of what sperm counts are doing in the rich world. (Countdown ECONOMIST vol. 405 no. 8814 December 8, 2012 page 81) There are two opinions: “stable” and “falling.” The most recent study is from France, (Joëlle le Moal and Matthieu Rolland publishing a recent HUMAN REPRODUCTION article) showing a decline of about 32.2% over 16 years ending in 2005 and about a 41% decline in well formed sperm over the same time span. That is on top of a previous decline of about 50% in the fifty years ending in 1992. I make that to be about a 70% decline in viable sperm, and the decline is getting faster in percentage terms from 1% a year to 2.5 percent per year. The absolute rate may not be changing a lot. If that is the case, we should be seeing negative sperm (I mean essentially no sperm) in about 40 years. That is not too long after the time when birth rates in the middle class the world over might approach zero as reckoned from other sources.
Of course there are those who dispute the study. Even among those who question the study mention is made that testicular cancer and male genital abnormalities are rising.
The only culprit suspected is environmental: somehow we are exposing boys to chemicals that feminize them. Thus the fall is real, which seems to me to be pretty well established. I was at a convention of fertility doctors about a year ago and a representative of the UN announced that the “normal” sperm count was being revised downward, which happens every few years. Nobody in the room cried, “Foul!”
Of course I do think it has to do with consanguinity. The middle class the world over has decided that consanguinity is a Bad Thing, and avoids it out to a degree of kinship so distant that a fertility penalty is incurred.
One does wonder why this should cause an increase in testicular cancer. I am woefully out of date on such things, but so far as we used to be taught one of the male genital malformations is undescended testicle. The testicle does not make its way into the scrotum, which means that it is warmer than it would be if it were normally positioned. This apparently increases the risk of testicular cancer.
So it all adds up. The best recent findings are consistent with what I have been saying. I do not expect the wakeup call to be heard soon.
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