Here is what a couple of catholic scholars say about this:
Raymond Brown and J.A. Fitzmyer, editors of the Jerome Biblical Commentary (2:482):
a woman: Most of the ancient commentators identified her with the Church; in the Middle Ages it was widely held that she represented Mary, the Mother of Jesus. Modern exegetes have generally adopted the older interpretation, with certain modifications.
In recent years several Catholics have championed the Marian interpretation. Numerous contextual details, however, are ill-suited to such an explanation. For example, we are scarcely to think that Mary endured the worst of the pains of childbirth (v. 2), that she was pursued into the desert after the birth of her child (6, 13ff.), or, finally, that she was persecuted through her other children (v. 17). The emphasis on the persecution of the woman is really appropriate only if she represents the Church, which is presented throughout the book as oppressed by the forces of evil, yet protected by God. Furthermore, the image of a woman is common in ancient Oriental secular literature as well as in the Bible (e.g., Is 50:1; Jer 50:12) as a symbol for a people, a nation, or a city. It is fitting, then, to see in this woman the People of God, the true Israel of the OT and NT.