January 31, 2010

Dr. Emily Oken
Assistant Professor of Population Medicine
Harvard Medical School
25 Shattuck Street
Boston, MA 02115

Dear Professor Oken:

Population Medicine is a new concept for me, but I found your name while looking into the fact that the average baby weight in the United States has been falling for a few years, and your department mission statement includes, “Using evidence to build a sound health policy.”  So here goes with some evidence.   

You are aware that babies are getting smaller, and I am quite sure you are aware that fertility is in decline.  There has been some recovery recently but still not up to replacement levels.  Less well documented so far as I know is an increase in hypospadius, decrease in penis size, falling sperm counts, increasing prematurity and increasing maternal deaths at childbirth.  I lump these all under declining fertility.  The question is the cause.  I saw a TV show the other night – Demographic Winter – which was hardly a peer reviewed journal article, but which did boast a number of authorities.  There was an unattributed statement that fertility is falling even in Africa and that 43 percent of the decline is due to birth control.  That leaves 57 percent unaccounted for.  The flame retardants in California may be affecting fertility, but I doubt that holds in most of Africa.

The cause is, in fact, established in the literature.  Over a thousand studies in animals and two good ones in humans relate fertility with kinship, or with size of mating pool, which amounts to the same thing.  I have put evidence and references on the enclosed DVD.  It is only 10 minutes long.  The bottom line is that, except for high degrees of inbreeding, closer than second cousins or equivalent, the nearer the kinship of couples the more grandchildren they have.  The decline in reproductive success with decreasing kinship is very steep, so that by 6th or 7th cousins there are not enough grandchildren for replacement. 

What may be worse news is that so far as the evidence I have seen, this effect does not manifest in the first generation.  It may well be that we all are born with a fixed degree of fertility so that if one’s ancestors chose their mates poorly we cannot reverse that in a single generation by choosing them well.  In other words, for those now alive fertility is immovable.  The only way to bring it back up to survivable rates is for couples to marry those who are sufficiently kin so that the children have adequate fertility.

When I was learning to be an airplane pilot, we had the concept of being, “In front of the airplane.”  In a car you pretty much decide what you are going to do from moment to moment.  In an airplane you have to know rather far ahead what you want to happen and take action when the goal seems distant.  Getting a generation ahead of the game is a challenge for anybody, and this is particularly true when there is nothing to look at but charts and numbers. 

I am not sure of this.  The numbers I have been able to find are as consistent with potential recovery in the first generation as they are with potential recovery in the second generation.  Either way, time is short.  We seem to be totally sold out on the idea that “more genetic diversity is always good” despite the fact that there is not a shred of evidence to support that, once one decides not to marry a sibling, first cousin or equivalent.  (The Iceland study referenced, which has the cleanest numbers, calculated kinship by going back 10 generations and counting ancestors.  That, of course, is not possible for most of us mortals.

I have been on the spoor of this phenomenon for many years.  I have posted, and continue to post, evidence on my website NoBabies.net where I also post correspondence.  I am sure enough of the phenomenon in broad stroke that I would cheerfully stake my life on it.  And I am quite sure that anybody with a conscience realizes the importance of the issue.  The problem is that, the evidence comes from many independent sources.  Each is sufficient but could be argued.  I even taught myself C language and wrote a computer program that follows the standard laws of genetics and accounts for just about all the evidence, although it takes the computer model more generations to run into trouble than happens in real life.  Nature has had more time and resources than I.  It is the combination of so many lines of evidence that is overwhelming. 

It is just a matter of standing back and connecting the dots.  But pretty much each dot is a different field.  Like the falling birth rates of babies.  Who is going to look at that and say, “Uh oh, we are being penalized for breaking up our little village mating units”?  And yet as part of a pattern it is intriguing, although not nearly so persuasive as the evidence on the DVD. 

Each dot has its own experts, its own power structure, its own heroes and heroines, its own traditions and its own prejudices.  There is much to do.

If you would be interested, if you would like to make common cause, if you want any clarification, if you would like a copy of the computer program or I can be of help in any way, please let me know.


M. Linton Herbert MD HMS ‘68
NoBabies.net and SilentNursery.com  

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