job interview

Just want to get some thoughts- Next week my family and I are moving back to my hometown since we are expecting twins :) - I have an interview at one of the hospitals, RN here, I will be a few days short of 19 wks- is it better to just be upfront about the pregnancy? Or wait to tell them?  I don't know if could not tell them, I would feel guilty about keeping it a secret- and to to add to it - it's getting pretty obvious that I'm pregnant....