I think that the reason for the differing conclusions is partly because they are talking about different things. The newer article is talking primarily about the morning after pill. The older article is talking about a different treatment, and was written before the MAP was approved by the FDA. I think the answer is that with addition of the ovulation test and different drug in the older article, the situation is less problematic than the normal pregnancy test and the MAP.
I don’t think that there has been a decisive statement on the issue from Rome, although I would be happy to be corrected if I am wrong. The reason for this, to my mind, is that the scientific/medical questions have not been completely answered. The Church has not done well out of getting mixed up in scientific questions in the past.
Slightly tangentially, this article from the National Catholic Bioethics Center is very good:
Sexual Assault and Abortion
This article from the same source, OTOH, is not at all tangential, and is also very good:
Getting It Right “The Morning-After”
The conclusion is basically, "It is permissible, then, for Catholic hospitals to provide their patients with morning-after pills if the following four conditions are met:
- The woman is not already pregnant from prior, freely-chosen sexual activity.
- The woman has been sexually assaulted.
- The woman has not yet ovulated (i.e. has not released an egg from her ovary into the fallopian tube where it could be fertilized by the attacker’s sperm).
- The morning-after pill can reasonably be expected to prevent her from ovulating. "
I think that is probably the most authoritative answer you are going to get at the moment, although of course the NCBC is not an official arm of the Church. It does say on the “About Us” page: “The Center’s staff consults regularly on life science issues and medical issues with the Vatican, the U.S. bishops, and public policy-makers, hospitals and international organizations of all faiths. Vatican agencies which regularly consult with the Center include the Congregation for the Doctrine of the Faith, the Pontifical Academy for Life and the Pontifical Council for Health Care Workers.”
–Jen