At least in the United States - it may be different in the *other* countries where he's paid for teens to have abortions.
State unequivocally that what he said is a total fabrication - that no preemie would simply be wrapped carefully in a blanket and presented for the mother to "decide"...
And be malpractice, I'd assume.
Don't take the nuanced approach. Deny the statement, make him revise it, and it will be a bit less fantastical (though still false) - deny it again.
Wash,. rinse, repeat, until the claim gets watered down so far it loses all shock value and he abandons that tack.
It needs to convey emotion, that physicians are astounded that any president would claim their profession as the modern-day version of the satanic child sacrifice ritual, to the alter of science, medicine + knowledge.