*If the pro-choice position is correct, then what was the mass of flesh in Mary's womb? When exactly did it gain the status of personhood? What was the state or condition with respect to Christ's flesh and blood prior to Him taking on these?
*If this mass of flesh makes up a human person because of its own special qualities and not because of a connection with something else, then that would lead to Nestorianism because the person of Christ would include two distinct persons.
*If this mass of flesh does not make up a human person in and of itself but takes on personhood at a later point in time, then that would lead to to Apollinarianism because Christ's human nature would temporarily be without a human soul. In order to consistently uphold the incarnation, the pro-life stance is a requirement.