March 31st is a special day; not only is it the third anniversary of my being "reborn" as the woman I truly was born as, but it is also International Transgender Day of Visibility.
We remember to recognize and celebrate this day, as it has significant meaning for all of us who are trans women and trans men. There are also quite a few of us who celebrate the day, me included, who were born intersex. As a matter of interest, if you find yourself in a group of 100 people, there's a chance that one or two within the group are intersex. Intersex people are born with physical and mental traits and attributes of both males and females.
In honor of this special day, I make myself visible by contributing and sharing some information presented by another sister that speaks to anyone who is interested, just what science has to say about being a transgender person.
Here goes:
New Insights Reveal Gender Identity is Deeply Rooted in Biology
For decades, transgender people have shared a simple truth: they know who they are. Now, neuroscience is catching up, providing solid evidence that gender identity is deeply rooted in the brain. Research shows that transgender people’s brains have unique traits, often aligning more with their gender identity than their sex assigned at birth. Studies on brain structure, function, genetics, hormones, and even epigenetics all point to the same conclusion: being trans is not a choice or phase but a fundamental aspect of who someone is.
Your Brain Knows Who You Are.
For as long as we’ve been studying the brain, people have wondered: what makes us who we are? When it comes to gender identity, science is providing clear answers – answers that reaffirm what trans people have always known.
The human brain is complex, and there is no single “gender switch” that determines whether a person will identify as male, female, or non-binary. Instead, gender identity appears to be shaped by a combination of factors, including brain structure, function, prenatal hormone exposure, and genetics.
Scientists have found that transgender individuals have distinctive brain structures and activity patterns that differ from their sex assigned at birth and often resemble those of their gender identity. These differences appear before hormone therapy, meaning they are not simply the result of transitioning. In fact, transgender brains are not just “male” or “female” but often form their own unique patterns, showing that gender exists on a spectrum rather than in a strict binary.
What Brain Scans Tell Us
One of the strongest pieces of evidence for the neuroscience of gender identity comes from MRI (Magnetic Resonance Imaging) studies. These studies allow researchers to examine the size, shape, and activity of different regions of the brain.
- Structural Differences in the Brain:
A well-known study of the BSTc (bed nucleus of the stria terminalis), a part of the brain linked to gender identity, found that trans women had BSTc sizes similar to cisgender women, not men. This area of the brain is believed to play a role in how a person experiences their gender.
More recent MRI studies show that transgender people’s brains have white and grey matter distributions that resemble those of their gender identity rather than their assigned sex at birth.
- Functional Differences in the Brain:
Scientists also use fMRI (functional MRI) to observe how different areas of the brain light up when performing tasks or responding to stimuli.
Studies have found that transgender people’s brains process emotions, social interactions, and even sensory experiences in ways that align with their gender identity rather than their assigned sex.
One experiment exposed transgender adolescents to a scent known to trigger sex-specific brain responses – trans girls (who were assigned male at birth) showed brain activation patterns that matched cisgender girls, not cisgender boys.
Together, these findings suggest that gender identity is not just a social construct but is reflected in the physical and functional architecture of the brain.
Hormones: Shaping Gender Identity Before Birth
The brain is not the only factor in gender identity – prenatal hormones play a crucial role in shaping how the brain develops.
During pregnancy, the presence or absence of testosterone influences whether the brain develops in a way that is typically associated with male or female traits. However, some people’s brains develop differently from their chromosomes, which may explain why transgender identities exist.
Key findings:
People exposed to higher levels of testosterone in the womb are more likely to identify as male.
People with differences in how their body processes hormones (such as androgen insensitivity syndrome) often experience gender identities that do not align with their chromosomes.
A 2024 study on prenatal exposure to diethylstilbestrol (DES), a synthetic estrogen, found that males exposed to DES in the womb were eight times more likely to be transgender women.
These results support the idea that gender identity is influenced by early biological factors, rather than being a choice or something shaped purely by the environment.
What Does This Mean for Trans People and Allies?
- Being trans is real – and it’s biological.
The scientific evidence is clear: gender identity is deeply rooted in biology. Transgender people are not “confused” or “making it up” – they are simply expressing the identity that aligns with how their brain and body developed.
- Trans people deserve respect, not debate.
Science confirms what trans people have always known about themselves. We don’t question whether left-handed people are “really” left-handed – so why do that to trans people?
- Gender-affirming care isn’t experimental – it’s backed by neuroscience.
Brain studies show that gender identity is stable and deep-seated. Supporting trans people in living as their true selves is not just about kindness – it is about recognizing scientific reality.
- If you’re trans, you are not alone.
Your identity is valid, and science backs you up. If you ever feel uncertain or struggle with acceptance, know that your brain and body are not broken – they are simply yours.
That is the information that was shared with me, and I sincerely hope that it will help to open the eyes of anyone who has questions on the reality and validity of being transgender.
Until next time,
Lauren
*Sources
Gaspari et al. (2024), Journal of Xenobiotics – “Early Female Transgender Identity after Prenatal Exposure to Diethylstilbestrol: Report from a French National Diethylstilbestrol (DES) Cohort” – https://doi.org/10.3390/jox14010001
Lee et al. (2024), Nature Human Behaviour – “State-level anti-transgender laws increase past-year suicide attempts among transgender and non-binary young people in the USA” – https://doi.org/10.1038/s41562-024-01581-6
Taylor et al. (2024), Archives of Disease in Childhood – “Interventions to suppress puberty in adolescents experiencing gender dysphoria or incongruence: a systematic review” – https://doi.org/10.1136/archdischild-2022-324283
Nguyen et al. (2019), Neuropsychopharmacology – “What has sex got to do with it? The role of hormones in the transgender brain” – https://doi.org/10.1038/s41386-018-0132-0
Altinay & Anand (2020), Brain Imaging and Behavior – “Neuroimaging gender dysphoria: a novel psychobiological model” – https://doi.org/10.1007/s11682-019-00177-4
Frigerio et al. (2021), Archives of Sexual Behavior – “Structural, Functional, and Metabolic Brain Differences as a Function of Gender Identity or Sexual Orientation: A Systematic Review of the Human Neuroimaging Literature” – https://doi.org/10.1007/s10508-020-01763-8
Very excellent Article Lauren. The human body, and the human mind, have go to be the most complex machine, and computer, ever devised. Almost infinitely variable and never 'one size fits all'. This is a perfect example of knowledge giving power. Power in self confidence, that, sadly, may do not want to take the time to better understand. I applaud your effort to help us all go to bed tonight, with more knowledge that we woke up with. Hugs
Dear Lauren. This is a very illuminating article based on scientific data that supports the fact that each of us is a person with unique characteristics. Heredity plus individuality, as Ortega y Gassett proposed. Genetics and development, we could say.
Very interesting, like all your writings. I found it very useful because it clarifies many previous ideas.
Thank you so much for this most excellent post Lauren. Not only have you given us some great information but you also included the references. Will you include this in your book too? Well done Sister! Big Hugs, Marg
Lauren, I really love the way that you posted this. It is just perfect and so needed. Thank you for all that you do for our community. You look so happy in your picture. You made my day. Big Hugs, Marg
Thank you, Lauren, for writing this wonderful article. Wouldn't it be wonderful to just go to a doctor and get a test that confirm what you knew was true all along. By the way you look wonderful!
Hugs Barbra
Hi Lauren, A very helpful article. You brought much info together into one spot so access was convenient and useful.
My wife knows I am trans, knows that I want to be a woman, but I am not sure she understand that I want to be a woman because I identify as one; at my soul level I am female.
I read her the article hoping to help her understand better that being trans is not my choice, that yes, truly I have been born trans. She listened and then complained that I have told her all these things previously so why did I need to tell her again. But I do believe hearing it from someone else with sources sited will be useful in slowly moving her to fuller acceptance and comfort with her husband being a woman at heart.
Blessings,
Charlene
Thank you Lauren what a good and thorough article. It definitely helped me to understand myself better
