New Job While Pregnant

I have a job interview coming up. I'm currently 15 weeks pregnant... do I tell them this during the interview? ((Granted I'm sure I'll have 1 or 2 dr. Appointments during training)) or do I wait for the job offer?

I'm stuck. Because I want to be upfront with them. But at the same time I dont want them to think 'oh she's going to become a mom, she may not want to come back after leave'

If I get this position I am hoping and praying this is going to be the place I retire from. And I'm 25 years old. I'm here for the long run.