The High Court has today started hearing evidence in a judicial review into puberty blockers and other medical treatments for young people suffering from gender dysphoria.
The legal challenge has been brought against the Tavistock and Portman NHS Trust in London by Keira Bell, 23, who claims that a gender clinic put her on puberty blockers when she was a 16-year-old girl suffering from gender dysphoria.
The IT engineer went on to experience transition regret and later reverted to living as female again.
She is calling for "institutional changes" that put the emphasis on proper psychological support for gender dysphoric youngsters, instead of medical treatments that may cause irreversible physical changes.
Speaking to Holly Willoughby and Phillip Schofield on ITV's This Morning on Wednesday, Miss Bell said she wanted more "explorative therapy" to address the causes of gender dysphoria, and for children "to be protected" and "actually listened to" by the professionals, instead of "being influenced to transition".
Tavistock runs the Gender Identity Development Service (Gids) where Miss Bell was treated. It is the country's only specialist clinic for gender dysphoric young people.
Speaking about the treatment she received, Miss Bell told This Morning: "It was just a process for me, because I found out how the process went through online forums and things like that so I was already aware of how the process worked.
"It was just a process, I wasn't necessarily happy or felt that I was being listened to. I was very focused on getting on the medical path."
She now believes she was rushed into medically transitioning and that she did not receive adequate psychological support for her gender dysphoria.
She continued: "There was no exploration of the feelings that I had, no psychiatric assessment. It was very brief and based on my recent past. There was no in-depth discussion.
"I can see now when I reflect back it was all very rushed, and I wish that there was some psychiatric assessment. At the end of the day I feel like it should have been explored into why I had those feelings and not just accepted for what they were."
Asked how she feels now about the irreversible physical changes caused by the treatment - which include a deeper voice - Miss Bell conceded that it was "going to affect me for the rest of my life".
"I have to make do with that and try and accept for how I am now and attempt to move on with that," she said.
She added: "It's true you can't change your sex. You can appear a certain way. If you'd had me on a couple of years ago I would have had the same story (as others), saying that it saved my life and I'm in a much better position.
"But the point is that teenagers can't comprehend how it's going to affect their adult life. People may say that it's helped them but for how long? For two, five, ten years? It's very flippant."
A Tavistock spokesman said: "GIDS (Gender Identity Development Service) is a safe and thoughtful service which puts the best interest of its patients and their families first.
"We won't comment on the ongoing proceedings and await the judgment of the court in due course.
"Surgical interventions are not available for under-18s. They can only be assessed by an adult gender identity clinic."