I'm sure the choir will love that sermon.
What's need, though, is for the Catholic Church and other pro-life groups to make clear that they don't want women who have had abortions to be consumed by guilt--they want them to be cleansed of it. The only way such women can be free of guilt is to recognize their mistake and discourage others from following in their footsteps.
If pro-life groups actively offered caring support for those who had had abortions, and solicited such people to join them, I would think that could do wonders.