In-Womb Development of the Transsexual Brain

Written by Tamara Sheehan


Nurture or Nature: What makes a Transsexual?

This is thwe big question that is faced by anyone who is or who knows a Transsexual. Because of a number of recent discoveries the balance has been tipped toward nature. There is now evidence that the “Gender Identity Dysphoria” (GOD) has it’s roots in prenatal biology (nature) and not in psychology (nurture).

New Discoveries Lean toward ‘Nature’.

What information about the brain has been newly discovered? When and by whom was it found?

In 1994, Dr. David Crews, Ph.D. published a paper with his findings regarding animal sexuality. He suggested that Transgender Behavior is shaped by embryotic sex hormones. In animals, they caused the brain to sexually develop a gender identity opposite that of the body. He suggested they could also influence the “Gender Identity” in humans.

            In 1995, a team of brain researchers in the Netherlands (J.M. Zhou, M.A. Hofman, L.J. Gooren and D.F. Swaab) dissected and compared the autopsied brains of a number of transsexual, homosexual heterosexual men & women. They found major differences between the Transsexual and non-Transsexual brains. The part of the brain that they studies was a region of the hypothalamus found at the base of the brain. It is called the ‘Central Subdivision of the Bed Nucleus of the Stria Terminalis’. They found that this part of the normal brain is 50% larger than the normal femal brain. Furthermore, it is 60% larger than the MtF Transsexual brain. In other words, the male to female Transsexual brain was vastly different than the normal male brain and very much like the normal female brain. They suggested that this may be part of the reason why MtF transsexuals often describe themselves as a woman trapped in a men’s bodies.

            Then in 1996 Arthur Arnold, a UCLA brain researcher confirmed the hormonal influences on human brain development. These findings corroborated the prior research done by Dr. Milton Diamond and Gunter Dorner in Germany and by Carl W. Bushong, Ph.D.

Normal Brain Developments

How does the brain develop in a normal male fetus?

All males start out as female embryos. However, somewhere between the 8th week to the 24th week a change to male occurs if the chromosomes are ‘XY’. They ‘XY’ chromosomes cause Testosterone to be produced and released by the body in the fetus body. In the fetal brain this testosterone is converted into a type of estrogen which masculinizes the male brain. The hormonal washed must be very precisely timed for this process to be successful.

How does the brain develop in a normal female fetus?

All female fetuses start out as female embryos. The ‘XX’ chromosomes order no hormonal wash to occur. The fetus, not touched by testosterone, remains female, both in body and brain.

Transsexual Brain Development

How does the MtF Transsexual?

Like the normal male embryo, the male to female Transsexual brain starts out female. Then between the 8th and 24th weeks, the ‘XY’ chromosomes introduce testosterone hormonal changes, but the hormonal washes as faulty. They are either insufficient or ill timed. When this happens, the fetus develops a male body. However, some of the default (original) female brain processes remain intact. Thus, the brain’s gender identity remain intact. Thus, the brains gender identity remains female. This means that Transsexual males whose process of brain masculinization was incomplete, Their default female brains still function. The degree of arrested development can vary. The orgininal brain circuitry that was missed in the masculinizing process provides a continuing feminine influence. This explains why many Transsexuals, biological males know, from as early as 3 years old, that they are actually members of the opposite sex.

How does the FtM Transsexual brain develop?

Like the normal female embryo, the female to male Transsexual fetus starts out as a normal female. Then a problem occurs somewhere between the 8th and 24th week. Even though the ‘XX’ chromosomes have ordered no hormonal washes to take place, testosterone is still introduced. For example: An errant fetal adrenal glad causes testosterone to be produced in great quantities. The fetus is washed with testosterone, against chromosomal orders. The fetal body remains female. However, if the errant wash is strong enough, the female fetus brain is re-wired to think as male. This explains why many Transsexuals, biological males know, from as early as 3 years old, that they are actually members of the opposite sex.

What is the job of the ‘XX’ and ‘XY’ chromosomes?

It seems that one of the jobs of the ‘XX’ and ‘XY’ chromosomes is to govern the introduction of testosterone into the womb. However, chromosomal influence is limited by the many glitches that can happen during the fetal growth process. This is why each human being possesses a unique mixture of male and female traits. Some of these mixes (eg: Transsexualism) make the individuals who have them significantly different from society’s expectations. This causes these people much confusion and suffering. Indeed, there are, in our world, many males who have ‘XX’ chromosomes and many females who have ‘XY’ chromosomes.

Being Transsexual is not a choice

What can be known about Transsexuals?

Transsexualism does not rise from being exposed, in childhood to the clother, toys, activities, and goals of the opposite sex. Nor are Transsexuals; sex addicts, morally corrupt or mentally ill. Transsexuals are simply people who have the body of one sex and the brain wiring of the opposite sex.

Being Transsexual IS NOT A CHOICE!

A Surprising Discovery

Can Transsexualism be classified as a gift/blessing?

The term ‘Transgender’ is an umbrella term that is used to identify and classify anyone who for any reason, does not fit within the boundaries of culturally accepted sexual stereo-types. These include: Gat, Lesbian, Bisexual, Androgonous, Crossdresser, Intersexual and Transsexual persons. Of these, the Intersexuals are the group most closely related to Transsexuals. In fact, they are probably more closely related than is generally recognized. Intersexuals are people who used to be called ‘Hermaphrodites’. They are persons who, physically posses, all, or parts of, both sexes. Transsexuals are individuals whose brains are the sex opposite their bodies. They have the ability, more or less, to experience both the male and female worlds. One could define Transsexuals as “Mental (Brain) Hermaphrodites (Intersexuals)”

            Thery are truly blessed by God as Gender Gifted. Each Transsexual is like a splash of vibrant color in a worl seemingly filled with only black & white. (Non-Transsexual males and females).


Sources for this article

Dunham, Wendy, “Biological Factors Influencing Transgenderism”, “Wendy’s World”, 1996

Zhou, J.N., Hofman, M.A., Gooren, L.J., Swaab, D.F., “A sex difference in the Human Brain and it’s relation to Transsexulity”, nature, 378:68-70, 1995.