Depends how you define "transition," but I haven't self-harmed since starting T. I have had some thoughts of suicide and self-harm - the last 6 weeks or so I was experimenting with a biweekly dosing schedule (I'd been weekly since I started) and this past weekend in the days before I was due for my shot I started getting brain fog, emotional instability, and self-harming thoughts. It was actually kind of a shock because the feeling had become so unfamiliar. It was like a flashback to when I was twelve and all of a sudden I started losing myself.

I was a regular self harmer between the ages of 14 - 18.
I tried to quit so many times and always relapsed soon after. I transitioned and I just sort of stopping doing it. I still come close every now and again, but I can't remember the last time I actually did it.

I am however, far more likely to get angry and punch something as a form of self harm and release.

I started when I cutting when I was 11, and it will be 10 years ago the end of August. I know that statistics say that both men and women self-harm in equal proportions, but when I think about myself cutting I always think of it as a feminine, teenage thing to do. Then I get mad at myself for doing it so I end up doing it again. It really is a vicious cycle. I cut, then I get mad at myself for doing such, so I end up cutting again. I try not to, but it is SO HARD. Nonetheless, I need to stop.

I began self harming when I was around 13, and stopped when I was 18.
At first it was a coping strategy, something that took my mind off the emotional pain and transformed it into something I could understand better: physical pain.
I was seeing psychiastrists and other mental health professionals to learn how to cope with my emotional pain better, and for the most part it didn't work.
What helped ultimately was starting to transition, which was when I was 18. After I had begun my physical transition, I no longer felt the need to replace emotional pain with physical pain. And when I felt the urge to cut, I used excercise as another means of "pain".
I'm proud to say I haven't cut in 6 years.

I don't know whether you count this, but I do - when I was in my mid-teens, I was anorexic (6'2" and weighing 105 pounds at one point) and it was partly tied up with body image and not wanting to grow up/out. For a completely unrelated reason, I got put on steroids for 2 months when I was 17, and that made me put on loads of weight, and my eating stabilised after that (I just started getting stoned instead...)

Eating disorders count clearly.

For me there was more to my episode, looking back it was also my body telling me you're not that 16 stone war machine you aspire too, at 18 I went down at 5' 10 to 8stone 8lb through not eating period, and was passing as a girl constantly without knowing, people told me though.  Looking back that eating disorder was my body rebelling against masculinization, but I actually like some of the viper in me, and it's worked out pretty good.  I've lived as a man until my mid thirties and it's a part of my personality I needed to be him but he can't take me any further.

I'd blame a complete lack of support and prejudice from loved ones, but I think this is all going to work out well.

I selected  "Had thoughts but never acted on them."

I've definitely always had thoughts, still do.  but I think it's my absolute zero pain tolerance that never let me act on the thoughts.  Instead I'll just burn stuff like paper.  just to watch stuff burn.  it's kinda calming for me.