Family Planning and "The Rhythm"


I have a question for the group but first some history.

When I was attending RCIA about three years ago a couple from the Church came in to share with the group how they live out ‘family planning’. My wife and I were eager to learn because we wanted to live our lives properly and in line with God’s will. So the husband starts going on about how they follow the wife’s rhythm. The wife explained this ‘rhythm’ as a temperature that they track in her body. When her temperature gets to a certain point then they know that they can enjoy intimacy without using condoms.

This is where I about lost my mind. (And I should add the conversation got heated.)

My point is this: The Church teaches us that anytime we enter into intimacy we should only do so with the desire to produce a child or to raise any barriers with the intent of preventing life.

My question is this: Am I wrong in believing that this is yet another form of birth control? In my eyes you are using the body against itself. If you have intercourse and are hoping NOT to become pregnant because you have properly tracked something; isn’t this the same as putting on a condom?

Please give me your opinions. I have waited too long to ask this question.


Wonderful question with a beautiful answer from our faith…

Here’s a quote from the Catechism of the Catholic Church… it’s long, but read it all… (see this link to the full section in the Catechism)

The fecundity of marriage

Fecundity is a gift, an end of marriage, for conjugal love naturally tends to be fruitful. A child does not come from outside as something added on to the mutual love of the spouses, but springs from the very heart of that mutual giving, as its fruit and fulfillment. So the Church, which is "on the side of life,"151 teaches that "it is necessary that each and every marriage act remain ordered per se to the procreation of human life."152 "This particular doctrine, expounded on numerous occasions by the Magisterium, is based on the inseparable connection, established by God, which man on his own initiative may not break, between the unitive significance and the procreative significance which are both inherent to the marriage act."153

Called to give life, spouses share in the creative power and fatherhood of God.154 "Married couples should regard it as their proper mission to transmit human life and to educate their children; they should realize that they are thereby cooperating with the love of God the Creator and are, in a certain sense, its interpreters. They will fulfill this duty with a sense of human and Christian responsibility."155

A particular aspect of this responsibility concerns the regulation of procreation. For just reasons, spouses may wish to space the births of their children. It is their duty to make certain that their desire is not motivated by selfishness but is in conformity with the generosity appropriate to responsible parenthood. Moreover, they should conform their behavior to the objective criteria of morality:

    When it is a question of harmonizing married love with the responsible transmission of life, the morality of the behavior does not depend on sincere intention and evaluation of motives alone; but it must be determined by objective criteria, criteria drawn from the nature of the person and his acts, criteria that respect the total meaning of mutual self-giving and human procreation in the context of true love; this is possible only if the virtue of married chastity is practiced with sincerity of heart.156

"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 orientation toward man’s exalted vocation to parenthood."157

Periodic continence, that is, the methods of birth regulation based on self-observation and the use of infertile periods, is in conformity with the objective criteria of morality.158 These methods respect the bodies of the spouses, encourage tenderness between them, and favor the education of an authentic freedom. In contrast, “every 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:159

    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. . . . The difference, both anthropological and moral, between contraception and recourse to the rhythm of the cycle . . . involves in the final analysis two irreconcilable concepts of the human person and of human sexuality.160

So, to answer your question in layman’s terms… the “rhythm of the cycle” (now most often referred to as “Natural Family Planning”) is designed by God. It doesn’t go beyond God’s creation or plan. Artificial methods of birth control (ABC) say to God “I want sex on MY terms”… and NFP says “I trust you, God”.

The mentality of the use is a big issue… NFP can, of course, be used with a “contraceptive mindset”… and that is not the teaching of the church. NFP is a gift from God given to couples who have prayerfully considered their fertility as a gift, and are asking God to help them abstain during the fertile phase of the cycle. ABC requires no sacrifice… NFP requires the sacrifice of abstinence.

I hope this helps a bit… :slight_smile:


I suggest you read the Catechism sections on the Sacrament of Marriage and the Sixth Commandment. Then also read Humanae Vitae and Casti Connubii. You can find these at the vatican website.

The Church does NOT teach that “birth control” is wrong. If it did, one would be obligated to have sex every day. One would be obligated to have as many children as possible until your body wore out. The Church doesn’t teach this, nor has it ever.

Birth control is the spacing of children for a just reason. One can absolutely delay children for a time or indefinitely if one has a just reason. Just reasons conform to the objective moral law. Meaning they are serious in nature and objectively moral in and of themselves.

Spacing children is not wrong. It is a moral good when there is a just reason-- the mother’s health being a primary one. Spacing children/avoiding children when necessary has never been forbidden by the Church.

Couples have always been able to do this by abstaining from intercourse. Our knowledge of when to abstain and how long to abstain has improved over the centuries. The natural family planning methods that observe a woman’s nature fertility cycle of mucus, cervical position, and/or temprerature cooperate with her natural cycle.

Contracepting alters an act of intercourse and frustrates its natural end. Abstaining does not. Abstaining is an act of chastity in marriage. Contracepting is an act of unchastity.


The Church teaches that each act must be ordered to procreation–the act is not altered. It need not be ordered to fertility. There is a difference.


I thought the Theology of the Body video series described this pretty well. Basically, NFP is okay’d by the church because it’s like a party invitation. When you have sex during your fertile cycle you’re sending an invitation to God to join the party. However, when you have sex during your non-fertile cycle you’re not sending an invitation to God but you’re okay if he crashes the party and shows up anyways. It’s when you use actual birth control that you’re basically sending an invite to God by having sex but then uninviting God to the party by using BC. Uninviting someone to a party that you’ve already invited them to is rude, which is why the church is against BC. Church is okay with NFP because not sending an invite isn’t rude, especially when you’re okay with the guest showing up unexpected.

Hope that helps! (and makes sense!)


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