I used to be a biologist and worked in microbiology for a few years. Then I got into computers and webdesign and found the creative stuff more comfortable/enjoyable work. Especially working for myself. I enjoyed being my own boss a lot.
Now I'm a full time fantasy figure sculptor and comic artist and I run my own business as a sculptor.
Never had any issues with my gender in any of my careers, I've worked a lot of different jobs... I don't recall at any point being barred from a career because of it. But then again with my personality if I wanted something and I was barred, I'd just go ahead and do it myself some other way anyway.
One thing I do think related to gender though... when I was younger I always had an intense desire to act and be an actor, but it was impossible for me to go and act the parts of a female. I couldn't bring myself to go for a career doing that, even though it was one of my greatest wants and I was extremely upset that I passed up on my auditions to get into a a good acting school. But the reason I passed up was very much because I was trans, and I couldn't face up to a career being known as a female actor. It's not that I refused to play a female - that wasn't the problem - it was the idea of the lifetime of 'playing' a female that I'd gone through already and it wasn't what I wanted in my aspiring career as well. Not to mention the roles women tend to get would have made me dysphoric too, and I don't really understand women on that level... so I know I could not convincingly play one other than visually. I guess in the end I still ended up in the creative arts, but doing what I do now I don't have to worry about my presentation.