Interview

I have a job interview tomorrow & I have no idea whether to tell them I'm pregnant or not. It's a bank in my local town. I am nearly 25 weeks and not showing much but besides the point, i just don't know what to do. I want to be honest but then again I don't want them to not hire me because of it. It would be such a great opportunity for our family but I'm in a dilemma here. Any advice?