"Mom Established" - which date do you use?

Question

I've seen these "Mom, est. 2019 [or 2020]" t-shirts that are so cute. But do most people use birth year? 
It seems odd to me because I consider conception date to be when I became a mom, but maybe I'm not getting something?

Answer

I think the date is for when baby is DUE not conceived.

Answer

I consider someone a mom by when they conceived but I would still get it as the year the baby was born.

Answer

You use whatever. It looks like it’s a shirt for an announcement so if you’re announcing a pregnancy, I’d use the year you conceived. If announcing a birth, use whichever date you want.