JOEL - The morning after pill can work by inhibiting ovulation and fertilization, the same as regular contraceptive pills, but the difference is that sometimes it works by preventing implantation of an already fertilized egg in the uterus.
Most medical professionals and Pro-Choice groups define pregnancy as beginning when a fertilized ovum, which has developed to the blastocyst stage, has attached itself fully to the lining of the uterus. On the other hand most pro-life groups believe a pregnancy and life begins at conception. The church also agrees that an individual life begins at conception in the biological sense (See this page), but has not made any official statement as to when a human soul begins(body + spirit). This difference in definitions will also of course carry over to what the definition of abortion is. If abortion means termination any time after conception, then the morning after pill could be considered a form of abortion if its effects prevent a fertilized egg from implanting itself. If abortion means termination after implantation, then the use of the morning after pill would not be considered abortion. However, it is impossible to know if the pill had its effects before or after conception. Because of this uncertainty the church would not accuse someone of having an abortion if they used it. At the present time, the church has taken a neutral stance on this form of contraception and leaves the decision to use it to married couples. The Church's general policy on birth control is the following:
"It is the privilege of married couples who are able to bear children to provide mortal bodies for the spirit children of God, whom they are then responsible to nurture and rear. The decision as to how many children to have and when to have them is extremely intimate and private and should be left between the couple and the Lord. Church members should not judge one another in this matter." (Handbook of Instructions)
Your friend will probably be able to keep her membership in the church, but if she was not married to the man she still would need to talk to her Bishop to confess the sin of fornication(or adultry) and begin the repentence process.