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Catholic Church

The Catholic Church states that its opposition to abortion follows from a belief that human life begins at conception and that "human life must be respected and protected absolutely from the moment of conception." Accordingly, it opposes procedures whose purpose is to destroy an embryo or fetus for whatever motive (even before implantation), but admits acts, such as chemotherapy or hysterectomy of a pregnant woman who has cervical cancer, which indirectly result in the death of the fetus. The Church holds that "the first right of the human person is his life" and that life is assumed to begin at fertilization. As such, Canon 1398 provides that "a person who procures a successful abortion incurs an automatic (latae sententiae) excommunication " from the Church, which can only be removed when that individual seeks penance and obtains absolution. The Church has affirmed that every procured abortion is a moral evil, a teaching that the Catechism of the Catholic Church declares "has not changed and remains unchangeable" since the first century. However, this claim of consistency of the Church on the question of abortion is disputed by a number of historians, such as John Connery, Ann Hibner Koblitz, Angus McLaren, and John Riddle. Until 1869, with the exception of the three-year period 1588–1591 during the papacy of Sixtus V, the Church treated abortion before quickening as less serious than abortion after quickening.: 362–364 The leading early Catholic theologians placed the time when an embryo took form as a human and could receive a soul as between 40 and 80 days; termination of pregnancy before 40 days was a "considerably lesser offense" than a later abortion.: 88–90, 136 : 112