Are there studies or articles providing evidence against the observations made?

On this website, I try to give evidence for some basic observations about transsexualism. The observations are grouped to answer the following questions:

Can we find objective evidence for the self-reported claims of transsexuals to have a different gender identity from non-transsexuals of their birth gender? Can we find neutral proof of the claims of transsexuals to belong to their experienced gender?

Is transsexualism a mental illness?

Do we know mechanisms that could cause transsexualism? Is the phenomenon of transsexualism consistent with what we know about the development of the human body and brain?

How can gender dysphoria be cured or eased?

The evidence can be found on the main reference pages:

What is transsexualism? | What causes transsexualism? | What helps?

More evidence: Disorders of sex development (DSD)

A summary of the findings of the reference pages is given here: Summary

A short essay on the biological basis of transsexualism is here: Biological basis

1. Brain functions and structures

   1. Brains of transsexuals show characteristics of their experienced gender (they differ from natal gender controls and are similar to target gender controls)

   2. Brains of transsexuals show characteristics that are part-way between male and female controls

   3. Brains of transsexuals are different – they show differences to either controls of their natal gender or to controls of both genders

2. Heredity and Genes

   1. Hereditary transmission of transsexuality is suggested by clustering and other distinctive features within families

   2. Genes of transsexuals show differences to natal gender controls

3. Other physical differences

   1. Physical differences can be found between transsexuals and natal gender controls

4. Psychiatric/psychological findings

   1. Transsexuality is not caused by mental illness and is different from psychopathological mental disorders

   2. Psychological profiles of transsexuals show characteristics of their experienced gender

5. Hormone exposure before and around birth can influence the sexual differentiation of the brain, including gender identity

6. Genetic factors can influence the sexual differentiation of the brain

7. Hormone treatment helps

8. Being out helps

9. Sex reassignment surgery helps

I believe there is sufficient evidence out there to regard the observations above to be true. These observations lead me to the summary as detailed on the creatively named summary page.

Human biology and psychology is very complex. Some of the difficulties are mentioned in the postscript on the summary page. I don’t think gender identity is a matter of black or white – there are also many shades of grey. When it comes to the origin of transsexualism and the feelings that transsexuals experience, a multi-factor cause is most likely, similar to many other health conditions. The cause will most likely include physiological factors such as genetic predisposition, epigenetics, gene expression, hormone exposure before and around birth and also social and cultural factors.

In order for the finds of a study to have some weight, the study needs to properly diagnose and differentiate transsexuals from non-transsexuals, have an adequate set of controls, include large numbers of people, have a selection of transsexuals that is representative, have as few drop-outs for follow-ups as possible, etc. This is not easy with a rare condition such as transsexualism.

It’s usually impossible to apply the gold standard of scientific studies (so-called double-blind studies) to the research of transsexualism. When it comes to gender identity, gender roles or gender expression, social factors come into play that should be accounted for. When looking at the mental state of gender dysphoria sufferers, the impact of discrimination by society must be considered. And so on… All evidence – for or against – must be seen in the light of these and more difficulties.

I appreciate any comments, amends and information about studies contradicting the observations above. I will publish/link any relevant study that I come across/that I’m being told about.

Please read the comments below for more information regarding apparently conflicting findings.

This observation is true even if only one aspect measured in the brains of both transsexuals and a control group of the same natal gender shows significant differences. The claim is not that all gender-dimorphic aspects of the brain are different in transsexuals when compared to natal gender control groups. Studies contradicting this observation would have to refute the specific findings of the studies provided, and ideally possess better credentials (such as larger number of participants, better systematics, etc.).

The latter part of the observation goes further, saying that certain gender-dimorphic structures of the brains of transsexuals resemble structures of their target gender. Here, again, studies expressing the opposing view would need to refute the exact findings provided.

Like observation 1, this observation is true even if only one physical aspect measured in both transsexuals and a control group of the same natal gender shows significant differences. The claim is not that all gender-dimorphic aspects of the body are different in transsexuals when compared to natal gender control groups. Studies contradicting this observation would have to refute the specific findings of the studies provided, and ideally possess better credentials (such as larger number of participants, better systematics, etc.).

As mentioned in the introduction to this observation on the reference page, it is quite complex to conduct and to interpret research on this issue. There are a number of different models of how mental illness could be related to transsexuality (e.g. not at all; caused by the discrimination encountered by transsexuals; caused by the same factors that cause transsexualism; mental illness causing transsexualism; transsexualism causing mental illness; etc.).

Because many or at least some transsexuals encounter social stigma, discrimination, lack of family support, abuse and guilt, these factors need to be accounted for when making like-for-like comparisons with normal control groups. Negative experiences of this kind are caused by external, social influences, not by the physiological condition of transsexualism itself.

In addition, one symptom of transsexualism is gender dysphoria, i.e. strong discontent with the own body and/or gender role, manifesting itself as unhappiness, anxiety, social distress or depression. This is very difficult to account for in studies. If psychological problems are part of the definition of a condition, measuring psychological problems will necessarily be distorted. There is no comparable control group either. It would be interesting to measure how well non-transsexual people do who are being raised forcibly in the wrong gender, but that is obviously unethical (except for old-style sexologists such as John Money).

I think these findings are pretty uncontroversial and have been proven in a multitude of human and animal studies over decades. As an example, a proof is provided in the existence of people affected by complete androgen insensitivity syndrome (CAIS).  Affected individuals are genetic males with a female gender identity due to body cells not being able to respond to testosterone.

The point here is that the articles listed support the view that the standard interventions of hormones, being out, and having sex reassignment surgery can help transsexuals. “Helping” in this context means that the overall happiness or quality of life of affected individuals is increased by the treatment. This can be measured by studies comparing happiness of transsexuals before and after the respective intervention, or by comparing two groups (as similar as possible), with one being denied treatment and one receiving treatment.

Studies comparing the quality of life of transsexuals with normal control groups are not relevant in this context. A study contradicting the evidence supplied would have to show that the quality of life for properly selected and diagnosed transsexuals is lower after treatment than it was before. If you know of such a study, please let me know.

It would be interesting to collect research to answer further questions in this context, such as

• What factors are associated with better outcomes?

• Can we subdivide transsexuals into categories that react differently to treatment? Could we then develop different, customised treatment approaches?

• Aside from the three mentioned treatments, are there other interventions that can help?

• Is there an ideal age for applying the treatments, i.e. does age affect the outcome?

• What is the best method to diagnose “real” transsexuals (individuals who benefit from treatment), i.e. to differentiate them from people who are likely to regret treatment at a later phase?