Mike says he finds himself with some strange bedfellows, as he can’t understand that most pregnant people identify as female.
The important word here is ‘identify’.
It is perfectly possible for a transgender female, who identifies as male to be pregnant, either though choice or violation.
He needs to add to his list of strange bed fellows Donald Trump, who is currently tearing up US legislation which allows transgender people to use toilets corresponding to the gender with which they identify.
So Mike, there may indeed be some pregnant men. The British Medical Association advice makes perfect sense to me.