Going back to work pregnant

Hello everyone. Had a question on how you might proceed. I finish my first maternity leave on Jan 20th and I’ll be 8 weeks pregnant with my second. It took us over a year to get pregnant the first time so we thought it might take awhile again... and it didn’t! So excited for the next baby but unsure how to proceed with telling or avoiding works questions.

My office has always joked about when is the second baby coming. What do I say that’s not a lie but not telling them? I want to wake until 12 weeks to let them know. I’ve come up with something like “it’s in the works”, or “we do want a second”. What did you tell work?

Thanks!