In the doctrine of the soul [Origen] was faced by a choice between three possible doctrines: (a) the Creationist view that God creates each soul for each individual as conceived and born; (b) the Traducianist view that the soul is derived, like the body, from the parents; (c) the Platonic Pre-existence theory, according to which immortal and pre-existent souls temporarily reside in the body. Creationism seemed to involve God in endless fuss; Traducianism seemed to endanger the transcendence of the soul in relation to the body by making it something corporeal. Pre-existence had the merit of making a theodicy possible which answered the Gnostics' complaint against the justice and goodness of the Creator. But the final result was a mythological theory of the creation which bore at least a superficial resemblance to the theory it was intended to refute; and orthodox churchmen were disturbed by a doctrine apparently more Platonic than biblical and strongly suggesting the corollary of transmigration. On several occasions Origen disclaims the myth of transmigration as false. Yet his own system presupposes a picture of the soul's course which is strikingly similar.
A. H. Armstrong, ed. The Cambridge History of Later Greek and early Medieval Philosophy. p. 191.
Interesting that in a sense the challenge of (b.) is now presented by evolution, and that at least since Darwin the Catholic Church has felt pressured into a stronger embrace of (a.). But the 'endless fuss' Origen referred to remains a problem, I think.