Catholic Teaching on Natural Family Planning
In its true meaning, responsible procreation requires couples to be obedient to the Lord's call and to act as faithful interpreters of his plan. This happens when the family is generously open to new lives, and when couples maintain an attitude of openness and service to life, even if, for serious reasons and in respect for the moral law, they choose to avoid a new birth for the time being or indefinitely. The moral law obliges them in every case to control the impulse of instinct and passion, and to respect the biological laws inscribed in their person. It is precisely this respect which makes legitimate, at the service of responsible procreation, the use of natural methods of regulating fertility.
The choice of the natural rhythms involves accepting the cycle of the person, that is the woman, and thereby accepting dialogue, reciprocal respect, shared responsibility and self- control. To accept the cycle and to enter into dialogue means to recognize both the spiritual and corporal character of conjugal communion and to live personal love with its requirement of fidelity. In this context the couple comes to experience how conjugal communion is enriched with those values of tenderness and affection which constitute the inner soul of human sexuality, in its physical dimension also. In this way sexuality is respected and promoted in its truly and fully human dimension, and is never “used” as an “object” that, by breaking the personal unity of soul and body, strikes at God's creation itself at the level of the deepest interaction of nature and person.
The right and lawful ordering of birth demands, first of all, that spouses fully recognize and value the true blessings of family life and that they acquire complete mastery over themselves and their emotions. For if with the aid of reason and of free will they are to control their natural drives, there can be no doubt at all of the need for self-denial. Only then will the expression of love, essential to married life, conform to right order. This is especially clear in the practice of periodic continence. Self-discipline of this kind is a shining witness to the chastity of husband and wife and, far from being a hindrance to their love of one another, transforms it by giving it a more truly human character. And if this self-discipline does demand that they persevere in their purpose and efforts, it has at the same time the salutary effect of enabling husband and wife to develop to their personalities and to be enriched with spiritual blessings. For it brings to family life abundant fruits of tranquility and peace. It helps in solving difficulties of other kinds. It fosters in husband and wife thoughtfulness and loving consideration for one another. It helps them to repel inordinate self-love, which is the opposite of charity. It arouses in them a consciousness of their responsibilities. And finally, it confers upon parents a deeper and more effective influence in the education of their children. As their children grow up, they develop a right sense of values and achieve a serene and harmonious use of their mental and physical powers.