Job interview question

I had my last baby in May and I had applied for a different position within the hospital I currently work at. I didn’t get this position, however the manager was very interested in my for a different position that they were in the works of creating. He and I have been in contact several times since my first interview in August. The position has finally come available and he yet again reached out to me. This position sounds right up my ally for what I want to do, and with work out better with my family life as well. However, I’m now 15 week pregnant... so big question do I say something in the interview? I feel like I need to be honest, and I know legally I don’t have to tell him, and I know if I do he can’t not hire me for being pregnant, however he could “find” other reasons not to hire me. I’m just at a loss... I don’t know what to do.