Increasing Low Birth Weight in America: Testosterone

6 posts / 0 new
Last post
James Michael Howard
James Michael Howard's picture
Increasing Low Birth Weight in America: Testosterone

The AP (Chicago) reported that "The percentage of U.S. women getting prenatal care has risen markedly since 1980, which should be good news, but the overall rate of babies being born with low weight has worsened, federal researchers said." This is derived from J Am Med Assoc 1998; 279: 1623. An editorial accompanying the JAMA article suggests "blacks and the poor - get no more care than previously..." This may be the reason, but I want to suggest another explanation, a biological explanation.

My work suggests human evolution is the result of increased testosterone in our species. Human males and females produce more testosterone than chimpanzee males and females, respectively. Furthermore, my work suggests testosterone increases periodically in civilizations. That is, where food and shelter are beneficial, people of higher testosterone will increase rapidly, compared to low testosterone people. They are more sexual and impulsive; they make more babies. They are bigger and reach puberty earlier; this is known as the secular trend. The secular trend is not due to better food. Black girls reach puberty much earlier than white girls, and there is no support that black girls eat better than white girls. We are currently witnessing an increase in testosterone in America.

Exposure to testosterone, during pregnancy, results in increased probability of low birth weight. This has been tested. Prenatal testosterone exposure reduced body weight of fetuses and newborn rats (Arzneimittelforschung 1984; 34: 780). Another study in sheep found that both fetal survival and growth were markedly impaired by prenatal testosterone administration (Metabolism 1978; 27: 253). Even more ominous is the finding that alcohol and testosterone, combined, induced low birth weight in rats (Tetratology 1989; 40: 335).

Testosterone is higher in black women than white women. "Serum testosterone was greater in AAF [African-American females] than in CF [Caucasian females]." (J. Clin endocrinol Metab 1996; 81: 1108). Low birth weight is more common among blacks than whites. More specifically, the numbers of high testosterone women are increasing more rapidly than the numbers of lower testosterone women. I suggest the JAMA findings indicate that the numbers of women of higher testosterone, and their problems with low birth weight offspring, are increasing rapidly, and increased prenatal care may not be a solution to the problem.

Copyright 1997, James Michael Howard, Fayetteville, Arkansas, U.S.A.

Soudabeh
Soudabeh's picture
Very interesting and

Very interesting and worrisome hypothesis.

Is your hypothesis regarding increased level of testosterone and its complications published or it is mentioned in a book? Could you provide references related to you work? How do you suggest we can reduce and why do you think is this increase happening in our society?

thanks

James Michael Howard
James Michael Howard's picture
Soudabeh wrote:

Soudabeh wrote:

Very interesting and worrisome hypothesis.

Is your hypothesis regarding increased level of testosterone and its complications published or it is mentioned in a book? Could you provide references related to you work? How do you suggest we can reduce and why do you think is this increase happening in our society?

thanks

Thank you for your response. It is published; has been since 1997. Go to www.anthropogeny.com/applications.html and look down the page. The key idea, that testosterone is increasing and causing problems, has been published in journals and newspapers a number of times. My work has been ignored, except in local newspapers, until I published my "Androgens in Human Evolution," Rivista di Biologia / Biology Forum 2001; 94: 345-362. (I put my work in my local newspapers to established a real record in a permanent place. I did not want my work to go ignored without establishing a record somewhere.)

I do not think a free country can reduce the increase in percentage of individuals of higher testosterone within populations. I doubt that even a totalitarian country can stop the secular trend. Women of higher testosterone will reproduce more rapidly than women of lower testosterone. Given time, women of higher testosterone will increase their percentage within a population, expose their fetuses to increased maternal testosterone, and generate the characteristics of this effect increasingly with time. Therefore, low birth weight will increase with time.

James Michael Howard
James Michael Howard's picture
Soudabeh wrote:

Soudabeh wrote:

Very interesting and worrisome hypothesis.

Is your hypothesis regarding increased level of testosterone and its complications published or it is mentioned in a book? Could you provide references related to you work? How do you suggest we can reduce and why do you think is this increase happening in our society?

thanks

This is just out. It directly supports my ideas from 1997.

Endocrine Abstracts (2006) 11 P570

Maternal testosterone levels during pregnancy are associated with offspring size at birth

SM Carlsen, G Jacobsen & P Romundstad

Norwegian University of Science and Technology, Department of Public Health and General Practice, Trondheim, Norway.

--------------------------------------------------------------------------------

Background: Animal studies have indicated that maternal androgen levels influence the intrauterine environment and development of the offspring. As human data are missing, we investigated the possible association between maternal androgens and offspring size at birth in humans.

Methods: Randomly collected parous Caucasian women (n=147) were followed prospectively through pregnancy. Maternal serum levels of dehydroepiandrosterone sulphate (DHEAS), androstenedione, testosterone and sex hormone binding globulin (SHBG) were measured at gestational weeks 17 and 33. The main outcome measures were weight and length at birth. Associations between maternal androgen levels and offspring birth weight and length were investigated using multiple linear regression modelling adjusted for potential confounding by maternal height, pre-pregnancy body mass index, smoking, parity, offspring gender, and gestational age at birth.

Results: Increasing maternal testosterone levels at week 17 and week 33 were both associated with lower birth weights and lengths. Accordingly, at week 17 an increase in maternal testosterone levels from the 25th to the 75th percentile was associated with a decrease in birth weight by 160 grams (95% CI; 29 to 290 grams), while at week 33 that estimate was 115 grams (95% CI; 21 to 207 grams). No similar associations were observed for DHEAS, androstenedione or SHBG.

Discussion: Increasing maternal testosterone levels during human pregnancy are associated with growth reduction in utero, and the weight difference compares with the impact that traditional factors, such as foetal gender or maternal smoking, have on birth weight. Newborn size characteristics are important predictors of a multitude of disorders in adult life. Hence, our identification of elevated maternal testosterone levels as a new indicator of intrauterine growth restriction in humans is important as it opens up the possibility to better understand the mechanisms involved in intrauterine growth. This in turn, may help to elucidate the mechanism(s) behind the foetal origins hypothesis.

Guy Sovak
Guy Sovak's picture
That Was a very interesting

That Was a very interesting Article,
Thanks for posting the abstract.
Guy

Teddy
Teddy's picture
Apart from testosterone check

Apart from testosterone check the effect of bisphenol-A (www.ourstolenfuture.org and at nlm.nih.org environmental toxicity). It is a hormonal disruptor and the problems with feminizing of the environemnt may be largely due to its proliferation -plastics industry.