Fr John Flader: contraception changes the marital act

Q: I know that the Church forbids the use of contraception in marriage, but if a couple are trying to avoid having a child, what is the difference between using contraception and using natural family planning?

First of all, it is important to be aware that there can be justifiable reasons for avoiding having another child, whether for the time being or even permanently.
Pope Paul VI said this in his encyclical Humanae Vitae (1968): “In relation to physical, economic, psychological and social conditions, responsible parenthood is exercised, either by the deliberate and generous decision to raise a numerous family, or by the decision, made for grave motives and with due respect for the moral law, to avoid for the time being, or even for an indetermined period a new birth” (n. 10).
That is, conditions such as the grave physical or psychological illness of either spouse, great economic hardship, etc., can justify spacing out births or even avoiding having another child altogether.
Returning to your question, if a couple have a sufficient reason to avoid having another child, what difference does it make whether they use natural family planning or contraception? It makes a great difference.
God’s plan in giving human beings the sexual power was that this power be used as an intimate expression of love in marriage – the unitive aspect – always open to the transmission of life – the procreative aspect.
In Humanae Vitae Pope Paul explained that the reason why contraception is always immoral is “the inseparable connection, willed by God and unable to be broken by man on his own initiative, between the two meanings of the conjugal act: the unitive meaning and the procreative meaning… By safeguarding both these essential aspects, the unitive and the procreative, the conjugal act preserves in its fullness the sense of true mutual love and its ordination towards man’s most high calling to parenthood” (n. 12).
When spouses practise natural family planning, they choose to have marital relations only during the infertile periods of the woman’s cycle. They do not close off their fertility and capacity to bring forth new life, but simply observe a cycle created by God himself.
They are always free to engage in sexual relations or not, so if they choose not to engage in these relations for some days each month, they do nothing immoral.
Moreover, their marital relations are acts of true love, of total, mutual self-giving. The couple reflect God’s total self-giving to man by giving themselves completely to each other, including their fertility, holding nothing back. Implied in their choice is the loving acceptance of any child God may send them.
In using contraception, on the contrary, the couple do not give themselves totally to one another. They give their bodies but withhold their fertility by using a physical or chemical barrier to avoid offspring, thus altering the very nature of the act. Not only is this contrary to God’s plan for the use of sexuality, it is not true love.
Pope John Paul II explains in his Apostolic Exhortation Familiaris Consortio (1981) that “the innate language that expresses the total reciprocal self-giving of husband and wife is overlaid, through contraception, by an objectively contradictory language, namely, that of not giving oneself totally to the other. This leads not only to a positive refusal to be open to life but also to a falsification of the inner truth of conjugal love, which is called upon to give itself in personal totality” (n. 32).
An act of marital union using contraception is an act of sex, but not of love. Couples who have been using contraception and later give themselves completely to one another without any barriers appreciate the difference keenly.
Moreover, couples who practise natural family planning for good reasons often find that their love for each other actually grows. In abstaining from marital acts for some days each month by mutual agreement, they grow in respect for each other and in self-mastery.