Sorry, I am not a physician, just a RN. FWIW, here are my thoughts.
The morning after pill is basically a double dose of birth control pills. It is not the abortion drug, RU486, which is given after implantation. Morning after pills must be taken within 72 hours of unprotected sex in order to be effective. Any fertilized egg which has implanted will not be aborted. The pill does not have that capability. The pills work like birth control pills which inhibit ovulation and/or make the lining of the uterus chemically inhospitable for a fertilized egg to implant. It is possible the egg may implant anyway. There are no guarantees. Sperm can remain active for days.
From a medical perspective, while a fertilized egg is human life it is not a pregnancy. Pregnancy begins at implantation. It's a hard sell to call the pills abortifacent from a medical standpoint. Those few days in between are a gray area. Fertilized eggs fail to implant at high rates. I don't know of any easy way to test for ovulation or the presence of a fertilized egg in the ER. The pills are given to prevent pregnancy.
The debate is more of a religious or moral nature. It is immoral to interrupt the life process and under what circumstances? Accurate definition of terms is important in order to be taken seriously. As medical science becomes more sophisticated it is a (pre)cradle to grave dilemma. Any hospital of a religious affiliation has the right to operate under its belief system.
Thanks for the additional information. It would seem, from both your posts, that there is not in fact any medical way to guarantee that ovulation has not occurred or will not occur around the time of a rape (or any sexual intercourse, for that matter).