What's so wrong about contraception that it's a mortal sin? Isn't the Church interested in the well being of people and the nation ?
A Christian married couple may and should be responsible in using the gift and privilege of transmitting life. (CCC 2368-2369, 2399). Sometimes social, psychological, and medical conditions are such that in the given circumstances an additional child would be a big, almost superhuman challenge for the couple. Hence there are clear criteria that the married couple must observe: Regulating births, in the first place, must not mean that the couple is avoiding conception as a matter of principle. Second, it must not mean avoiding children for selfish reasons. Third, it must not mean that external coercion is involved (if, for example, the State were to decide how many children a couple could have). Fourth, it must not mean that any and every means may be used. (YOUCAT 420)
The Church recommends Natural Family Planning (NFP) as methods of deliberately regulating conception. These are in keeping with the dignity of man and woman; they respect the innate laws of the female body; they demand mutual affection and consideration and therefore are a school of love. (CCC 2370-2372, 2399). What does this mean?
The Church pays careful attention to the order of nature and sees in it a deep meaning. For her it is therefore not a matter of indifference whether a couple manipulates the woman’s fertility or instead makes use of the natural alternation of fertile and infertile days. It is no accident that →NATURAL FAMILY PLANNING is called natural: it is ecological, holistic, healthy, and an exercise in partnership.
On the other hand, the Church rejects all artificial means of contraception—namely, chemical methods (“the Pill”), mechanical methods (for example, condom, intra-uterine device, or IUD), and surgical methods (sterilization)—since these attempt to separate the sexual act from its procreative potential and block the total self-giving of husband and wife. Such methods can even endanger the woman’s health, have an abortifacient effect (= cause a very early abortion), and in the long run be detrimental to the couple’s love life.
Pope John Paul II describes “contraception” (as opposed to “the regulation of births”) as follows: “When couples recourse to contraception . . . they manipulate and degrade human sexuality—and with it themselves and their married partner—by altering its value of total self-giving. Thus 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.” POPE JOHN PAUL II (1920-2005), Apostolic Exhortation Familiaris Consortio, number 32.