The Magisterium
The Church also, fulfilling the role given it by Christ as the identifier and interpreter of apostolic Scripture and apostolic tradition, has constantly condemned contraception as gravely sinful.

In Humanae Vitae, Pope Paul VI stated, “[W]e must once again declare that the direct interruption of the generative process already begun, and, above all, directly willed and procured abortion, even if for therapeutic reasons, are to be absolutely excluded as licit means of regulating birth. Equally to be excluded, as the teaching authority of the Church has frequently declared, is direct sterilization, whether perpetual or temporary, whether of the man or of the woman. Similarly excluded is every action which, either in anticipation of the conjugal act, or in its accomplishment, or in the development of its natural consequences, proposes, whether as an end or as a means, to render procreation impossible” (HV 14). This was reiterated in the Catechism of the Catholic Church: “[E]very action which, whether in anticipation of the conjugal act, or in its accomplishment, or in the development of its natural consequences, proposes, whether as an end or as a means, to render procreation impossible is intrinsically evil” (CCC 2370). “Legitimate intentions on the part of the spouses do not justify recourse to morally unacceptable means . . . for example, direct sterilization or contraception” (CCC 2399). The Church also has affirmed that the illicitness of contraception is an infallible doctrine: “The Church has always taught the intrinsic evil of contraception, that is, of every marital act intentionally rendered unfruitful. This teaching is to be held as definitive and irreformable. Contraception is gravely opposed to marital chastity, it is contrary to the good of the transmission of life (the procreative aspect of matrimony), and to the reciprocal self-giving of the spouses (the unitive aspect of matrimony); it harms true love and denies the sovereign role of God in the transmission of human life” (Vademecum for Confessors 2:4, Feb. 12, 1997).