Telling family you’re pregnant

I just need advice.

I told my sister, dad and step mom in our group chat after my ultrasound.

I have never had a good relationship with my mom but I feel like she has the right to know from me instead of my sister or my grandmother (when I tell her).

I just feel that telling my mom is going to open a can of worms I don’t want to deal with. Her wanting to be around and help me out when the baby gets here and I don’t want any of that from her. She’s caused a lot of trauma in my childhood and I don’t want that negativity nor do I want more memories to pop up if she’s around.