I've changed over the years from cautious to open right away. It might have helped me too that I've been inpatient for my eating disorder (now recovered from after 20 years) and for trauma therapy regarding childhood abuse more than 10 times for 2 to 6 months each time. That intensity, plus all the groups, helped me realize that my story is not so unique and I need not be embarrassed. I think I got to the point that I don't need to hide that fact that I was abused or any of the related crap that goes with it. I have no problem telling a t everything in the first visit. I don't need to build up trust bc I go in to therapy expecting (trusting) the t will be professional and that's all I need from a t. (in other words, keep confidential what I say, have the education their degree indicates, have general or specialized knowledge in my issues (which I look for before making the appointment) ) To me, going in to the t for the first time is like going in to any doctor the first time. I trust them to do their job.