What would PAIF do? Job related

Snarling Fox

I know I'm over thinking this and it's a little premature but I like to pretend I'm ready for the possibilities. 

Not letting IF get in the way of my normal life, I applied for an internal job. It's somewhat of a small promotion. So far, I've gotten good reviews and tons of encouragement from my peers. I think the interview went well. And I'm hearing there's a good chance I'll  get one of the open positions. Here's the but - I'm just a little over 5 weeks now and my first ultrasound is over a week away. Last time no hb developed. They should be making announcements some time next week (before u/s day). 

If I do get the job, should I let them know I'm pregnant right away? Or should I wait until after first tri? It's a large company and I'm staying in the same department. There's no shortage of coverage. Im leaning towards not saying anything, in case it turns out like the last time. But I also don't want to come off like I hid this from them as I move into a new job. Wwyd?