[The_Colonel]

> No, it doesn't cover trans men who will give birth to become the baby's father.

Why?

> If we give advice for "expecting mothers" not to sleep on their backs...

Yes, but

a) you rarely need such differentiation.

b) I'm pretty sure people would understand what is meant from the context.

[AlecSchueler]

> Why?

Because they're fathers, not mothers.

> a) you rarely need such differentiation

How common does it need to be before precise language becomes preferable?

Around one in a 100 couples with children are same sex couples, at least in the US. Acceptance rates of homosexuay vary of course and laws have been lagging behind, so we can expect this number to raise as acceptance grows. Inclusive language is part of that acceptance.

You also have many families with adoptive mothers who didn't give birth to their children.

> b) I'm pretty sure people would understand what is meant from the context

And I'm pretty sure even children can understand the term pregnant person. I'm surprised that so many people here are confused by it

[Athari]

> Around one in a 100 couples with children are same sex couples, at least in the US

How many of these couples include a pregnant trans male though? I think the term "pregnant person" would be a hard sell in particular.

[The_Colonel]

> Because they're fathers, not mothers.

They gave a birth to the child, something only mothers can do.

> You also have many families with adoptive mothers who didn't give birth to their children.

Well that's my point. Using the term "mother" is just fine for them. That doesn't make a necessity to always differentiate by emphasizing that a given woman is "birth mother" / "birth person". In most cases (including LGBT/trans) using the term "mother" is fine and there's no need to go more specific than that.

> And I'm pretty sure even children can understand the term pregnant person. I'm surprised that so many people here are confused by it

It's not confusing, use it, if you wish, but I prefer the term "mother".

What people are annoyed with is the language police, imposing your preferred usage on others. The host being pushed to apologize for using the term "mother" is just absurd.