It's not "gendered language", it's "sexed language".

This is a context - indeed THE context - where sex is what matters. Therefore it makes sense to use sex-based terminology. There is no need for "gender" roles to be attached to that sex-based use. You are not projecting any societal preconceptions about what a "woman" or "mother" is - you are using the terms strictly in the biological sense.

Whatever hang-ups a female enby or TiF has about being called a mother need to be put at the door before they start attempting sexual reproduction. If they can't do that, they're probably not ready.

Freddie McConnell(?) recently lost her appeal to try to be named the "father" of her child. The court made the very clear judgement that it was wrong to assume that "mother" was a gendered term - it was the specific role in reproduction, and there was no need to assume the gender of a mother, and it was incorrect to assume that only "women" could be mothers.

That was an interesting piece of line drawing - sure, we let you identify as a "woman", and that might be a "gender identity", but that's no reason to couple actual sexual function to gender identity. By TRAs own logic, transmen can be mothers, have vaginas, uteruses, breasts... Those are not "gendered". Seems like a reasonable compromise to me, if these people could compromise. Sure, maybe you can be "he", but you're still the mother.