I am 5 months pregnant and have a job interview. Should I tell them at the 1st interview?

I have been having a hard time finding a job in general (thus, I find myself already 5 months pregnant and finally having a job interview, I'm also showing so I can't hide it very well with an outfit)...On one hand I want to be honest with them from the get go, on the other hand, though it is illegal to not hire a pregnant woman, many companies could find a way around it. Should I not divulge that I am pregnant until I am actually offered the job? That seems sort of deceitful. This is sort of a tough dilemna! I'd like some advice please:)