Like, it wouldn't be trans exclusionary. The group description would be "for anyone who has or has had a cervix is welcome! That includes cis women, transmen, non-binary people with a cervix! Discussion about said cervixes and how they have impacted your life encouraged!"
It's a title they've fostered off on to us so why not use it and see how long it takes for them to try invade the space anyway?
Also, don't get me wrong, I hate it, but part of me just wants to see them cry transphobia anyway and be rebuffed. I know it didn't work for 2XChromosomes but they feel slowly and completely before it got so bad.
edit: to be inclusive to women with MRKH, OvaryHavers might be better. I will add here ladies, I'm not sure we will come up with a term that can fit all of us. That's kinda the point