A Discussion on the Relationship Between Gender Identity And Prenatal Exposure to Diethylstilbestrol (DES) in 46XY Individuals 

   Introduction

 

 

Created by Kathy Cochran

 

 

Diethylstilbestrol (DES) is a synthetic estrogen, once promoted for use in the prevention of miscarriages. The purpose of this website is to examine a side effect of DES which the medical community and pharmaceutical companies are reluctant to discuss. DES is now defined as an endocrine disrupting chemical or EDC. Humanity has already learned several very painful lessons form the great DES experiment but is this particular Pandora's box actually empty? The topic of this website is extremely complex so please continue with an open mind and be prepared to study as I present a substantial amount of scientific data. Notably, the Gender Identity, Research and Lectures pages.

 

In 1999, Dr. Scott Kerlin began researching the effects of DES on the health of genetic males who had been exposed prenatally. A substantial amount of research had been done on genetic women who had been exposed but relatively little had been done on genetic males. When it became apparent that a significant portion of his research group were either transsexual, transgendered or intersexed, he began to explore the possibility of a connection between prenatal DES exposure and gender variance. Dr. Kerlin is not the first researcher to note a correlation between DES exposure and feminized behavior in genetic males, studies go back as far as 1973. However, Dr. Kerlin has delved much deeper than those who came before. (See the timelines page of this site and the links and files section of the DES-Sons group.)

 

KWMR radio interview with Dr. Scott Kerlin ( MP3, 5.2 MB download )
KWMR radio interview with Dr. Dana Beyer ( MP3, 3.7 MB download )
A new book by Deborah Rudacille, The Riddle of Gender: Science, Activism, and Transgender Rights

Dr. Beyer's and Deborah Rudacille's Interview with WAMU Radio The Science of Gender, (Starts at the 16 Minute point, requires Real Player)

Dr. Scott Kerlin, Prenatal Exposure to Diethylstilbestrol (DES) in Males and Gender-Related Disorders,:Results from a 5-Year Study

Publications by Christine Johnson, MSEE, MES
Gender Identity Research and Education Society, Atypical Gender Development - A Review

 

 

Because DES is highly effective at reducing testosterone production, it was also used in the treatment of prostate cancer. During prenatal development, sufficient testosterone is essential for the sexual differentiation of the brain. Male and female brains are structured slightly differently and yes, numerous animal studies have proven that it's possible to influence the development of some structures by manipulating the prenatal hormone balance of the fetus. Animals with cross sexed brain structures also display cross sexed behavior as adults. Is there a human equivalent? Gender dysphoria is the medical term used to describe people who are born one sex but have the feeling that they should have been born the opposite sex. For some of us this feeling is so intense that we undergo gender reassignment surgery. The common term for us is Transsexual.

 

Lets begin with a quote from the well known Merck Manual. The concept that prenatal hormone levels affect the sexual differentiation of the brain and are in part responsible for the development of our gender identity has become so well accepted that even the Merck manual states, "Although biologic factors, such as gender complement and the prenatal hormonal milieu, largely determine gender identity, the formation of a secure, unconflicted gender identity and gender role is influenced by social factors, such as the character of the parents' emotional bond and the relationship that each of them has with the child". Merck is a major pharmaceutical company and was one of the numerous manufacturers of DES.

 

In 1995, a group of researchers from the Netherlands published the following study. "A Sex Difference in the Human Brain and its Relation to Transsexuality".  The report begins with the following paragraph. "Transsexuals have the strong feeling, often from childhood onwards, of having been born the wrong sex. The possible psychogenic or biological etiology of transsexuality has been the subject of debate for many years. Here we show that the volume of the central subdivision of the bed nucleus of the stria terminalis (BSTc), a brain area that is essential for sexual behaviour, is larger in men than in women. A female-sized BSTc was found in male-to-female transsexuals. The size of the BSTc was not influenced by sex hormones in adulthood and was independent of sexual orientation. Our study is the first to show a female brain structure in genetically male transsexuals and supports the hypothesis that gender identity develops as a result of an interaction between the developing brain and sex hormones".

 

Some people have argued that the changes in brain structure noted in the above paper may have been caused by exposure to hormones as an adult. In 2000, researchers examined the brains of people who, for a variety of reasons had been exposed to similar hormone regimes as transsexual people regularly take and did not find the brain structure in question to be affected. Males had a typical male brain structure and females had a typical female brain structure. Others have argued that the sample of brains studied is to small. One should keep in mind that although the human sample is small, studies on other mammals is extensive. In fact, DES is now used as a positive control when researching the effects of other endocrine disrupting chemicals. For instance,. "Sex difference eliminated (males behave like control females)"

 

Since then, many of the worlds top researchers who study gender identity have signed a document titled "Definition and Synopsis of the Etiology of Adult Gender Identity Disorder and Transsexualism". This document states that "Transsexualism can be considered to be a neuro-developmental condition of the brain". It also states the following. "Factors which may contribute to an altered hormone environment in the brain at the critical moments in its early development might include genetic influences (Landen, 1999; Coolidge et al, 2002) and/or medication, environmental influences (Diamond et al., 1996; Whitten et al., 2002), stress or trauma to the mother during pregnancy (Ward et al., 2002; Swaab et al., 2002)".  Please note the word medication in the above quote.

 

The comment about genetic influences is also apt because in addition to existing data, in 2005 a paper titled "Sex steroid-related genes and male-to-female transsexualism" was published, and discussed the genetic coding of the hormone receptors of 29 transsexual people. As it turns out they exhibited a genetic variation which is quite common amongst many people but may make them more susceptible to certain types of endocrine disruption.

 

Lets look at a few more quotes. "Gender Benders & Endocrine Disruptors around You".

"Abnormal development of gender-specific sexual behavior in DES offspring (feminized males and masculinized females), suggesting that DES caused abnormal sex differentiation during fetal development " and "Abnormal development of male sexual behavior "

(Elizabeth Lee Vliet, MD quotes an excerpt from "It’s My Ovaries, Stupid, pgs. 83 – 107 Scribner, 2003 " )

 

This is from the chemical reference standard, “Dictionary of Organic Compounds, 6th Edition (1996)”. In reference to diethylstilbestrol, it  includes the following under its stated adverse human health effects. "Causes male impotence and transsexual changes particularly in offspring exposed in utero". Can't get much more direct than that.

 

I've contacted numerous neuroscientists around the globe. Most were kind enough to respond and of those who did, none were surprised.

 

Here is one of numerous quotes from University Professors found on the lectures page of this website.

Geert J. De Vries  Hormonal Control of Sexual Differentiation
"Gonadal hormones profoundly influence brain physiology and behavior in vertebrates. During development, these hormones determine whether brains will function in a typical male or female fashion."  

 

The above quotes are just the tip of the iceberg, a summary of a very complex issue. The subsequent pages of this website provide much more information.

 

One obvious question is, what do the pharmaceutical companies have to say about this issue? From my own personal experience the answer is in essence "no comment". I've sent them the link to this website and although I know they have visited it, (I can see the Domain Name of those who visit) not once have I ever received a reply or comment.

 

How about our governments and Health Care providers? The responses I've received from Health Canada are very polite and oh so carefully worded. I've never received a response from the Centers for Disease Control. However, displayed on the CDC website is a portion of a paper titled  Psychosexual Characteristics of Men and Women Exposed Prenatally to Diethylstilbestrol  Unfortunately the researchers who published this paper somehow forgot to include transgendered/transsexual people in their study. Despite my prodding, the CDC hasn't been inclined to post a link to the complete paper, I wonder why?

 

Could it be this? Embedded in the rest of the paper is the following statement: "Briefly, 1% of the poten-tially eligible women (exposed or unexposed) and 3% of the men (5% exposed, 2% unexposed) had died before the combined study was implemented ". This paper, which the CDC holds in such high regard, is reporting that the mortality rate of DES exposed males is 2.5 times higher than the control group.

 

 

 

Despite more than 50 years of research which include articles such as this:

"Clinical toxicology of estrogens.
Westerholm B.
PIP: This paper reviews both minor and major adverse reactions caused by estrogenic substances (natural and synthetic, steroidal and nonsteroidal) of which diethylstilbestrol is the prototype of nonsteroidal synthetic estrogen. Minor side effects include nausea, breast tenderness, and excessive cervical secretions (most common), headache, and water and salt retention (less common and often eradicated by lowering estrogen dosage). Vertigo, yeast infections, depression, and photosensitivity are other minor effects. Major side effects are discussed in some detail. Major effects include those on the endocrine system (e.g., feminization in boys and men and precocious puberty in girls); breast tumors; endometrial carcinoma; ovarian tumors; hypertension; thromboembolism; blood clotting excesses; various metabolic effects (including lipid metabolism and carbohydrate metabolism alterations); liver changes (bile alterations and neoplasms); porphyria; melanoma; and effects on a fetus in situ during maternal estrogen administration. In general, lowering doses of estrogen should help eradicate or alleviate most of these effects."

 

DES is largely ignored by the government run health care systems of the world. They seem more interested in doing damage control for the major pharmaceuticals than in public health. 

 

One may be tempted to say, well that's all very interesting but so what? Sooner or later all of us exposed will pass on and then the problem will be solved. As it turns out there is a bit of a twist.

 

We now know that many chemicals including DES, DDT, PCB's and dioxins can either mimic natural hormones or otherwise interfere with hormonally sensitive tissues. They are referred to as endocrine disrupting chemicals or EDC's. Increasing numbers of researchers are seriously examining the health effects of exposure to these chemicals and the curious thing is that DES comes up over and over again in their research papers.

 

In this example, the effects of bisphenol A are being researched. DES is used as a positive control which means that if the researchers don't see behavioral or physiological effects with the DES exposed group then they haven't performed their experiment correctly. The study clearly shows a sex reversal in behavior and in an area of the brain known as the locus coeruleus (LC). Kubo, K, O Arai, M Omura, R Wantanabe, R Ogata, and S Aou. 2003. Low dose effects of bisphenol A on sexual differentiation of the brain and behavior in rats. Neuroscience Research 45: 345-356.

"Kubo et al. report that at levels beneath the 'safe' level established by the EPA, bisphenol A (BPA) exposure in the womb alters sexual differention of the brain and behavior in rats. Their study adds to the weight of evidence that health standards for exposure to this molecule, used to make polycarbonate plastic and now a ubiquitous contaminant found in many people, need to be strengthened dramatically."

 

Some readers may be familiar with a book titled "Our Stolen Future". The authors of this book, Dr. Theo Colborn, Dianne Drumanoski and John Peterson Meyers examine the problems associated with EDC's. A quote from their website states "Normal brain development is heavily influenced by a host of hormonal signaling systems. Thyroid hormones play a major role. The sex steroids (testosterone, estrogen, etc.) contribute to, among other things, sexual differentiate of brain centers, and thereby, to the development of sexual identity and sexual behaviors". ”What is emerging from this research is that brain and behavior are likely to be the most sensitive endpoints vulnerable to endocrine disruption”.

A paper written by Bernard Weiss, further illustrates this (department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York). Sexually Dimorphic Nonreproductive Behaviors as Indicators of Endocrine Disruption, "Because sexual differentiation of the brain is guided primarily by the actions of gonadal hormones but with thyroid hormones involved as well, disturbing the appropriate balance of these hormones during development by exogenous agents will produce morphological, neurochemical, and behavioral abnormalities. McEwen succinctly noted that the brain-endocrine axis is in a delicately balanced state during development: "Exogenous mimics can play havoc with brain development and differentiation"
 

A quote from the Canadian Medical Association Journal (CMAJ) v.163 , i.11 28nov00 "Prenatal or early postnatal exposure to certain environmental pollutants has been associated with learning and behavioural abnormalities. In some cases, there is evidence that these neurologic abnormalities may be due to an endocrine mechanism. For example, a single low dose of dioxin during the development of the hypothalamic- pituitary-gonadal axis in the rat has been shown to produce a feminizing effect on the behaviour of male offspring, reflecting altered sexual differentiation of the brain."

 

And just to prove that these chemicals do indeed exist in our diet, a quote from a recent article in the Independent. "More than 50 dangerous pesticides contaminate Britain's food, official tests reveal. All have been found to be poisonous or are suspected of causing cancer or having "gender bender" effects by international regulatory bodies."

 

And are they affecting humans in distinctly measurable ways? A quote from a recent article in the Guardian "Tests showed that women with higher levels of four different phthalates were more likely to have baby boys with a range of conditions, from smaller penises and undescended testicles to a shorter perineum, the distance between the genitals and the anus. The differences, say the authors, indicate a feminisation of the boys similar to that seen in animals exposed to the chemicals."

 

Check out the Environmental Health News Website for a comprehensive listing of news articles dealing with the environment. For instance, try doing a search on "gender bend" or "endocrine disruption". You may be amazed by what you discover.

 

Also the Conclusions page of this website lists numerous articles discussing environmental feminization of various species.

 

Compared to worldwide reports of global warming, declining semen quality and rising birth defects, drugs and chemicals which have the potential to interfere with the sexual differentiation of the brain may not seem very important, but in my opinion they represent an integral aspect of a much bigger issue. The health of the only home we have, planet Earth. (Image complements of NASA)

 

 

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[Introduction] [Definitions] [Discussion] [Lectures] [Gender Identity] [Intersex] [Table1] [Table2] [Table3] [Research] [Genetics] [Questions] [Conclusions] [Links] [Timelines] [Responsibility]

 
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