In case of rape a Catholic perspective permits the use of means to prevent fertilisation where there is no danger of causing an abortion. The Catholic perspective, however, does not permit the abortion of an embryo already conceived. For this reason, it is very important that people seek help as soon as possible after the rape. The logic of the Catholic argument is as follows. Whilst contraception is not permitted in the case of a loving married couple because this would defeat the purpose of marriage, in the case of rape a very different relationship exists between the two parties. The woman who has been raped has not freely chosen to have sexual intercourse with her attacker and indeed has been violated against her will by an aggressor. A person is always allowed to defend themselves against such an attack. Preventing the possible fertilization of one of the woman's ova by the attacker's sperm is a legitimate part of this defence against the attacker. Therefore, medications which specifically work to prevent fertilization can be administered. What may not be administered are medications that have an abortive effect resulting in the destruction of an already fertilized egg, which is now an embryo. Once fertilization has taken place, the newly formed embryo is considered an innocent human life, a human being worthy of the same respect as all other human beings.