New job doesn’t know I’m pregnant

Hello!

I lost my job the beginning of December. I was just offered a new job but obviously did not share my pregnancy. I’m almost 18 weeks and not really showing.

When should I tell them? This job is a great opportunity and I’d like to come back after maternity leave but I won’t be eligible for FMLA.

Has anyone been in this position? I’ve been in HR for a long time and I know it’s not always the best when a new hire tells you they’re expecting.

Any advice would be great!!