April 2, 2015

Does the effects of hormones on transgender people prove that crossdreaming has a biological component?

Is crossdreaming purely psychological or does it have a biological basis? Hormones may give us part of the answer.
Illustration: xrender

There seems to be a general agreement among most psychiatrists who treat dysphoric male to female (MTF) crossdreamers and crossdressers that there is one "drug" that will alleviate some of their distress: Estrogen/oestrogen (the most important being estradiol/oestradiol), often misnamed the "female" hormone.

Estrogen and anti-androgens reduce possible emotional distress caused by crossdreaming

Harry Benjamin, the grand old man of transgender research, noted as early as 1966 that both "transvestites" (i.e. crossdressers) and non-transitioning transsexuals could benefit from taking estrogen, as it could be "helpful emotionally" or "needed for comfort or emotional balance".

There is little literature on this, but my contacts among therapists and activists confirm the well-known "secret" that doctors continue to prescribe estrogen to MTF crossdreamers, even when they do not plan to transition.

Some doctors  also prescribe antiandrogens, i.e. drugs that reduce the flow of testosterone, "the masculinizing hormone", in the bloodstream, or reduces the brains ability to make use of "T".

There are also antiandrogens that stop regular testosterone from being transformed into the more active dihydrotestosterone. The effects of antiandrogens are somewhat similar to the effects of estrogen: a reduction in the effects testosterone has on the mind and body.

Some doctors also combine the use of estrogens and antiandrogens to achieve the desired effect: a reduction in emotional distress and dysphoria. Crossdreamers who self-medicate on herbal alternatives often look for similar combinations, like when taking pueraria mirifica (for an estrogenic effect) and saw palmetto (for an antiandrogenic effect).

The two sides of sex hormones

It is important to note that you may influence the effects of sex hormones like testosterone and estrogen in two ways:

1. You may increase the amount of testosterone or estrogen in the body by way of pills or injections.
2. You may stop the body from absorbing the relevant hormones.

This relationship between "production" and "reception" of sex hormones is well known in sex research. It is not enough to produce the relevant hormones. You also need the appropriate receptors to absorb and make use of them. If a child with an XY "male" chromosome combination for some reason fail to develop the sufficient number of testosterone receptors, that child may develop a female body and mind.

It is also important to keep in mind that testosterone and estrogen are not really "male" and "female" hormones. A male fetus actually needs estrogen to produced the amounts of testosterone needed to develop a male body. The fetus transforms estrogen into testosterone, then the testosterone triggers the development of male sexual characteristics. At puberty another boost in testosterone turns boys into men.

On average men may have up till 20 times as much testosterone as women.

[SIDEBAR: On male to female hormone replacement therapy]

T - the sex driver

Testosterone has more than one task, though. It  is also a driver for sexual arousal in both men and women.

Many women experience a reduced libido after menopause, mainly because their bodies produce less testosterone. Since women can be as erotically charged as men, we have to conclude that it is not the absolute amount of testosterone that decides such arousal, but a relative one: Women need much less testosterone to experience the same level of arousal as men.

You could say that men and women's brains are calibrated differently as regards the effect testosterone has on their minds.

"You feel happier"

The use of estrogen and antiandrogens will normally not make the crossdreaming disappear in male to female crossdreamers. The dreams of becoming their target sex (the "other" sex) will still be there. However, the obsessive nature of the crossdreaming is much alleviated.  Crossdreamers report a new sense of normalcy, a sense of peace, and some report a new feeling of mental harmony and even euphoria.

Male to female crossdreamer Moon put it this way in her guest blog post here at Crossdreamers.com:
"All you know inside is that you do genuinely feel better about yourself. You feel happier, more in control, able to put your thoughts about being a woman into perspective. The obsessional thoughts are very much reduced and your thought patterns more logical. Estrogen is working for you, it makes you feel much, much better."
The key phrase here is "obsessional thoughts".

Crossdreaming does not have to be obsessive. For many it is not. But for some both crossdressing and/or the consumption of crossdreamer erotica becomes obsessive to the point of dominating their lives in a very distressful manner. Some of them reach a phase where they can hardly think of anything else. They neglect work, friends and family.

Why do sex hormones have this effect?

Illustration: macromediam
But why does taking estrogen and/or antiandrogens work? Why do they have this calming effect? These questions go to the very heart of one side of the crossdreamer debate, namely to what extent crossdreaming is a purely psychological phenomenon (often referred to as "a fetish") or whether it has some kind of biological component.

(And please not that I write biological component. There are very few researchers or activists in the transgender field who think gender dysphoria is the end result of biological factors only. This applies to my line of thinking as well).

The testosterone-poisoned brain

One of the leading experts on crossdreamers  is Dr. Anne Vitale.

She has suggested that MTF crossdreamers produce too much testosterone. This triggers an effect where their bodies turn the excess testosterone into estrogen, and it is this estrogen that feeds their interest in feminization.

I must admit that I find this argument complex and hard to follow.

If the MTF crossdreamer brain is actually producing feminizing estrogen, this should reduce their level of anxiety, achieving much of the same effect as doctors seek when giving them estrogen and antiandrogens.

That discussion requires a longer argument than there is room for in this blog post, though. See sidebar for my interpretation of Vitale.

[SIDEBAR: On Anne Vitale's theory on testosterone-poisoning in MTF crossdreamers]

A much simpler model would be to say that the MTF crossdreamer/transgender brain is -- to a smaller or larger degree -- calibrated more like a female brain as regards the use of testosterone and estrogen. Since the body of the MTF crossdreamer produces a level of testosterone needed for a "regular" male brain, this leads to a kind of "testosterone-poisoning".

This would at least partly explain why their crossdressing may become so erotizised, and why their erotic transformation fantasies can become obsessive.

When you reduce the level of testosterone, the mind/body-system is normalized and the crossdreamer achieve a better mental balance.

We might speculate that MTF transgender who report less arousal of this sort have relatively speaking lower levels of testosterone. I doubt very much that this is the whole story, though. Social conditioning and repression definitely play a role in how transgender conditions play out -- of that I am sure.

Arguments in support the fetish approach

The fact that estrogen and antiandrogens have such a strong effects on MTF crossdreamers makes it harder to defend the position that crossdreaming in particular, and transgender conditions in general, are exclusively the results of childhood erotic imprinting, i.e. what many  refer to as "a fetish".

However, I have seen that some have argued that the fact that crossdreamers feel better about themselves after taking antiandrogens proves that this nothing but a fetish: Taking antiandrogens is seen as a kind of chemical castration, removing the sex drive from the equation. When you remove the sex drive, you also remove the desire to be a woman. Therefore it has all been proven to be a purely psychological and sexual phenomenon.
Illustration: zorabcde

The problem with this line of reasoning is that in most cases the desire to become the target sex does not disappear when you take such drugs. It only becomes less sexualized.

If this proves anything at all, it is the exact opposite: Remove testosterone and you are normally left with a less sexually obsessive, but nevertheless real desire to be a woman.

Doctor  Charles Moser makes a relevant argument  in his critique of the autogynephilia theory of Ray Blanchard. Note that the "autogynephilia" theory is not the same as the fetish theory. Blanchard dismisses the idea that crossdreaming is caused by a fetish. Still, Moser's argument makes sense in a fetish context as well:
"If the impetus for gender transition is a paraphilia (autogynephilia), then reduction of the sex interest should decrease the desire for the transition. Low testosterone, either due to anti-androgens or other causes, is associated with decreased sexual interest in individuals with or without a paraphilia. Estrogen acts to decrease testosterone levels, but most transsexuals are prescribed anti-androgens to reduce further their testosterone level, often to the undetectable range. The result is often decreased sexual interest, as expected, but this rarely causes any discomfort or regret. Most MTFs report their drive for gender transition is unabated; Blanchard (1991) also observed this same phenomenon.

If autogynephilia were a paraphilia, we would expect that MTFs would want estrogens to feminize themselves, but decline anti-androgens or report that they disliked the effect. This is contrary to the observation that MTFs request and like the effects of anti-androgens."
A placebo-effect only?

In discussions over at Crossdream Life I have found people arguing that the positive effects of taking hormones are caused by some kind of placebo-effect, in the sense that the drugs have no real effect on the psyche and that it is "all in the mind".

The reason for this would be that even if the crossdreamer does not plan to transition, taking feminizing hormones represents some kind of affirmation of the desire to become a woman. After all, this is also what trans women do when they transition, even if the dosage might vary.

I am not going to dismiss the argument that affirmation of one's sense of self is extremely important for the emotional well-being of transgender people. The acceptance of lovers, family and friends often reduces the feeling of dysphoria, and if your doctor and your significant other accept that you take these pills, that will most likely have a positive effect on your sense of well being.

Still, I find the idea that this is all about placebo unconvincing. After all, the argument does not address the main point here: that there is something that causes this desire to be a woman. A placebo-effect cannot be the cause of a placebo-effect.
Illustration: areeya_ann

Some argue that this "something" is some residual effect of the psychological, erotic, imprinting. That is: Even if you remove much of the sex drive by removing the testosterone, there is still some kind of  psychological "imprint" left. Wanting to become a woman has gradually become a part of your personality, a part you can no longer get rid of.

Most who suffer, or have suffered, from severe gender dysphoria can tell you how unconvincing this argument is, but I can see that it may make sense to non-dysphoric crossdreamers.

Vitale makes an observation that can help us out here. She writes:
"It is not unusual for some patients, feeling better after starting hormones, to believe they are cured and no longer need to continue the medication. Unfortunately what they experience is a quick return of their gender dysphoria."
Clearly some of her patients have believed that the hormone therapy has somehow "cured" their crossdreaming, now that the more obsessive characteristics have gone. They stop taking the pills, believing the change is permanent.

If the positive change had only been an effect of them believing that the pills had such an effect (as opposed to physically having an effect on the psyche), stopping taking the pills would make no difference. Yet, the dysphoria reappears, telling us that the effects of the hormones on the psyche are real.

But what about the female to male crossdreamers?

There is another way of testing the idea that crossdreaming is based on more than an erotic imprinting. The female to male  transgender provide us with another clue in the crossdreamer mystery. We can use their very existence to triangulate an answer.

Anne Vitale does not include female to male crossdreamers and crossdressers in her transgender typology. Ray Blanchard does not even believe that they exist.  They do exist, as I have proven beyond any reasonable doubt here, here and here. Female to male transgender may also get aroused by the idea of being their target sex, by way of expressing masculinity and through crossdressing and erotic fantasies.

As sexual desire and hormones go, the female to male crossdreamers are not perfect mirror images of the male to female ones. The reason for this is that testosterone is the hormone of sexual desire for all human beings, men and women, transgender and non-transgender.

Let us for the sake of argument say  that the reduction of dysphoria or distress in MTF crossdreamers taking antiandrogens is caused by a reduction of libido only.  Well, the FTM transgender  increase their levels of testosterone. This should lead to an increase in libido. If the dysphoria is driven by sexual desire only, taking testosterone should make FTM crossdreamers feel worse.

The fact is, however, that FTM crossdreamers and transgender people taking testosterone report the same kind of well being and increased mental balance as their MTF counterparts. Many, if not most of them, report an increase in libido, but this does not make their gender dysphoria more intense, as it should, if the dysphoria was simply the end effect of a sexual fetish or paraphilia.

Is this proof?

Does all of this prove that crossdreaming is more than the effect of some psychological erotic imprinting? I hesitate to use the word proof. The fact is that we know too little about the interactions between genes, hormones, hormone receptors, epigenetics, psychological, social and cultural factors to say anything absolute conclusive about what causes gender variance.

Still, to me the effects of E and anti-T on MTF crossdreamers are clear indications of biological factors playing a role in the development of such variance.

I would also like to add that even if we ultimately find that crossdreaming is partly caused by the calibration of hormone receptors in the brain, and that MTF crossdreamers have more "feminine" brains than non-transgender men, this does not mean that all MTF crossdreamers are transsexual women trapped in men's bodies.

If the hormone story tells us anything it is that there is no absolute binary. Even such simple factors as hormones introduce a complexity that goes far beyond a simple binary: There are androgens and estrogens; there are different levels of hormone production; there are different levels of "free" testosterone that may actually affect the body and mind; the number and capacity of hormone receptors will also vary.

Furthermore, there are many other factors, psychological and biological, that will influence how such variation plays out in real life. In other words: The effects estrogen and antiandrogens have on MTF crossdreamers  do not mean that all of those who react positively to this kind of hormone treatment are "women trapped in a men's bodies".  We have found that around a third of MTF crossdreamers experience severe gender dysphoria, and I am not convinced that even all of them are transsexual, regardless of how you define that term.

Ultimately every crossdreamer will have to listen to his, her or their heart when it comes to exploring and defining their  identity.

See also:

What brain science says about M2F transsexuals

Genes, hormones, sex and gender identity

For an alternative, pro-imprint, take on the crossdreamer/hormone issue, see Third Way Trans' blog post "Breaking the testosterone/dysphoria cycle"


On male to female hormone replacement therapy

On Anne Vitale's theory on testosterone-poisoning in MTF crossdreamers


Harry Benjamin: The Transsexual PhenomenonSymposium Publishing, Düsseldorf, 1999,

Ai-Min Bao  and Dick F. Swaab: "Sexual differentiation of the human brain: Relation to gender identity, sexual orientation and neuropsychiatric disorders" Front. Neuroendocrinol. (2011), doi:10.1016/j.yfrne.2011.02.007

Ophelia Bradley:"They Need Labels": Contemporary Institutional and Popular Frameworks for Gender Variance, ScholarWorks at Georgia State University 2010 (with a very good overview on research on transgender neuroscience and effects of hormones)

Louis Gooren: "The biology of human psychosexual differentiation" Hormones and Behavior 50 (2006) 589–601

Lauren Hare, Pascal Bernard, Francisco J. Sánchez, Paul N. Baird, Eric Vilain, Trudy Kennedy, and Vincent R. Harley: "Androgen Receptor Repeat Length Polymorphism Associated with Male-to-Female Transsexualism" BIOL PSYCHIATRY 2009;65:93–96

Daniel Klink and Martin Den Heijer: "Genetic Aspects of Gender Identity Development and Gender Dysphoria", from B.P.C. Kreukels et al. (eds.), Gender Dysphoria and Disorders of Sex Development:  Progress in Care and Knowledge, Focus on Sexuality Research,
Springer, New York 2014

Baudewijntje PC Kreukels and Peggy T Cohen-Kettenis: "Male Gender Identity and Masculine Behavior: the Role of Sex Hormones in Brain Development" in  Hormonal Therapy for Male Sexual Dysfunction, edited by Mario Maggi,  John Wiley & Sons, Ltd. 2012

Charles Moser:  "Blanchard's Autogynephilia Theory: A Critique", Journal of Homosexuality, 57:6, 790-809

GID-info on normal male and female hormone levels.

Robert M. Sapolsky: "The Trouble with Testosterone", in The Trouble with Testosterone and Other Essays on the Biology of the Human Predicament, Scribner, New York 1998.

Anne Vitale: "Testosterone Toxicity Implicated in Male-To-Female Transsexuals? Some thoughts." T-Note 15 2009.

Anne Vitale: The Gendered Self, Flyfisher Press, Point Reyes Station 2010.

Jaimie F. Veale,  David E. Clarke  and Terri C. Lomax:  "Biological and psychosocial correlates of adult gender-variant identities: A review" Personality and Individual Differences 48 (2010) 357–366

Kevan Richard Wyliea, Robert Jr Fung, Claudia Boshier and Margaret Rotchell: "Recommendations of endocrine treatment for patients with gender dysphoria", Sexual and Relationship Therapy, Vol. 24, No. 2, May 2009, 175–187


  1. Jack as usual thoroughly well researched and thought out. I have noticed that in myself (now in my early fifties) that the waning of any erotic component in my cross gender expression has produced no reduction in my desire to go about my life as a part time woman. If anything the feelings have only grown stronger with age and I am more firmly convinced that there is pre existing biology at play that becomes coupled with erotic overtones at puberty which often helps only to confuse the trabsgendered person.

    There are numerous examples of people such as Renee Richards, Katherine Cummings and Virginia Prince (to name some notable examples) who started out convinced they were heterosexual cross dressers. All ended up transitioning with no regrets. Therefore I feel it would be facile to assume that all this is about fetish and nothing else.

    Even proponents of transition through the AGP theory such as Anne Lawrence define the arousal impetus as being part of a more complex overall picture.

    The hardest part for those afflicted with this condition becomes using the appropriate level of response. Sometimes all that is required is an appropriate level of cross gender expression with or without hormones to manage the dysphoria. The pivotal issue becomes not overshooting and then regretting.


  2. "The pivotal issue becomes not overshooting and then regretting."

    I agree, and I can see why this makes some people look for some kind of litmus test of transsexuality everyone should agree on. Given the complexity of sex and gender, I do not think we will ever find one.

    This is why it is -- as you imply -- so important to be cautious and give transgender people of all colors and shades time to figure themselves out.

  3. Benjamin prescribed hormones to Doris (one of his first 10 oatients) who had a history of dressing with sexual arousal.. She eventually divorced and lived out her life as a woman without resorting to surgery. She was well read on the subject and correspondended for many years with Benjamin.

  4. “A much simpler model would be to say that the MTF crossdreamer/transgender brain is -- to a smaller or larger degree -- calibrated more like a female brain as regards the use of testosterone and estrogen...” I find that a very attractive explanation, Jack. Is that an idea in the published literature, or your own suggestion? In a sidebar you attribute it to “local sexologists”. In my own case, I’m trying to understand why crossdressing interests first surfaced in adolescence but not before. If puberty is the final peak in testosterone secretion, when the brain is most sensitive to such hormonal changes, perhaps that’s when T-production overwhelmed by brain hormone receptor system.

  5. @dabrela

    I wish I could give you a more precise reference than this, Dabrela. This is indeed an idea I have got from a group of Scandinavian sexologists. I am still looking for a decent literary reference, however. I will let you know.

  6. @dabrela

    I have added some more references to the literature list above.

    The following presentations may also be of interest. Much of the research on receptors is based on experiments with rats. Rats are not human, but our common evolutionary origin may give rise to similarities.

    Alford Laboratory Powerpoint

    J.-N. Zhou, M.A. Hofman, L.J. Gooren and D.F. Swaab have written on hormone receptors among transsexuals. See also this paper by Swaab.

    Unfortunately the old controversy regarding androphilic and non-androphilic trans women makes it hard to draw any final conclusions regarding MTF crossdreamers.

    Moreover, the findings are controversial for a wide variety of reasons, the main one being -- as I see it -- that such research is often too uncritical of the way cultural preconceptions may influence research results.

    It seems to me that researchers still know to little about receptors to make final conclusions about any of this. See for instance this paper.

  7. Thanks very much, Jack. I'll follow up those references, perhaps even try to write something about this myself. But I must admit I struggle with these densely scientific papers; it's good to have people like you who can summarise the findings in layman's terms!

  8. As usual, your articles are a source of information and comfort for me (comfort in the knowledge that I am not alone in feeling this way and that it is not so taboo that people aren't doing studies on cross-dreaming). The use of hormones to help balance a cross-dreamers mind by making it less erotic centric, sounds like it could be a benefit to me and I think I will look into trying it out. I don't think the cross-dreaming part of me is an obsession, but it is very distracting at times, especially when it becomes arousing and I guess to a point, I don't want to admit that it is obsessive. Even if it doesn't work for me, it will be worth a try.

  9. @Flexor

    I do get some very positive reports from crossdreamers regarding this, even if some -- like Moon -- report some important side effects as well, including bodily changes.

    Ask a doctor/sexologist first!


  10. Nothing new here. Conveniently missing from this post is,

    1. That there is no given way which hormones will figure within how the individual comes to think.

    2. The distinction between directly sexually constituted thoughts and deeply engrained emotional attachments derived from sexual thoughts.

    3. The role sexuality has in how hormones figure for and is judged by the individual, in light of the sexual predispositions distinguished in 2.

  11. Anonymous

    you are correct in that the ingestion of hormones will have an effect in the physical sense and on brain chemistry which is why each person should proceed with absolute caution. Hormones are not candy and I think they should be avoided unless prescribed by a qualified doctor to help relieve strong and persistent dysphoria. If you can function without them you would be advised to do so.

  12. Thank you! Thank you! Thank you! You expressed exactly what I have been trying to put into words for a very very long time. I really think your explanation is hitting the mark. While, it may not explain everything or everyone, it certainly rings true for me and is a great start. Please do not stop your writing and sharing and analysis.

    Your site has been instrumental in keeping me sane, keeping me connected, helping me sort myself out. My marriage has benefited, my life has benefited, and you may never know how important your writing has been to me. Sally's writing too! Thanks Jack.

  13. @Anonymous

    Thank you for your kind words. It helps to know that what we do here can make a difference, and I am glad that our crossdreamer discussions have helped you and your wife.

    Maybe I will live to see the day when we do not need sites like this one. I hope so. But until then I will continue to write about crossdreaming.

    (And Sally sends her best to you and your wife!)

  14. This is really great ! Crossdreaming is becoming obsessive for me sometimes (I describe it as waves with peak period) and I would love to be able to wear female clothes longer because now that would just make me aroused. It is so powerfully erotic to me that it's becoming uncomfortable. I really don't know if I need to take hormones, it's really scary but at least there's a hope that I can control myself or understand if I need to go further.
    And yes, I have a grown a light dysphoria with many parts of my body. I find females bodies so beautiful while I think mine is just hairy and big ^^`.

  15. I didn't know that taking estrogen and antiandrogens work in alleviating excessive cross dreaming for people transitioning into the other sex. I would expect that this would be very beneficial so that transgender people struggling with crossdreaming can come to be the people they want to be while still living normal, balanced lives. They are trying to become the normal person they want to be, so taking these hormones to alleviate the excessive and sometimes erotic thoughts of becoming the other gender will definitely allow them to transition easily and go about living their lives. Thanks for the insight on cross dreaming and what it is! http://www.genemedics.com/hormone-replacement-therapy-for-women-michigan/

  16. I know most of you will not like this but I just have a desire to have my nuts cut off.
    I don't even want to become a woman.
    I just don't want to remain a man...


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