When did you inform your company that you are expecting?

Hi! May i know when is a good time to share with your company that you are pregnant? Is it after first trimester? I have worked in current company for 2 years and this is my second pregnancy. First one was with a different company and this will be my rainbow baby so i am very careful this time. Also, is it normal if some days i feel light cramps and some days i don't feel cramps at all? I felt like i'm overthinking by not feeling the cramps all day long 🫣