Question about birth control

I have a question and am, frankly, a little embarrassed to ask…but here goes.

I’ve read Humanae Vitae, understand its themes and principles and believe them true. I’ve studied the Theology of the Body, both in private and at a Christopher West seminar and I’ve listened to many audio teachings on the subject.

I do have one nuance that I haven’t been able to understand logically. Here it is…NFP targets those times where pregnancy is not possible or, maybe more accurately, where the chance of pregnancy is reduced. Essentially, the deposit is being made to a place where life can not occur. The intention is to avoid pregnancy.

I fail to see a difference between this method of birth control and coitus interrupts where the intention is to avoid pregnancy, the chance of pregnancy is reduced and the deposit is made to a place where life can not occur.

Can someone help me to understand where the difference lies?

I think the answer I’ve seen most consistently given (as this question comes up often) is pretty much this: ‘Because The Church says so.’

Forgive me if I am mistaken.

Here is a great article on this topic on

My own thoughts: Using birth control says “I am in control.” Using NFP says “God is in control.” I have conceived on Cycle Day 24 while following the rules to the best of my ability and trying to prevent pregnancy. When I found out I was pregnant, I accepted it as a blessing. NFP can also be used to achieve pregnancy when couples are struggling with infertility. A local couple tried various methods and medications for seven years, then started using NFP and conceived on their third cycle.

NFP can be misused if a couple has the wrong intent, as it says in the above article, but artificial birth control can NOT be used with RIGHT intent. (Note that I am talking about birth control, not contraceptives that are used to cure other medical issues.)

I think that may be the only answer… seems flawed.

What about Summa Theologica where St. Thomas Aquinas concluded that there’s no conflict between faith and reason, and faith is through wisdom?

No… the ‘deposit is being made’ specifically to a place where new life can occur! (It’s just at a time in a woman’s cycle during which conception is highly unlikely.

I fail to see a difference between this method of birth control and coitus interrupts where the intention is to avoid pregnancy, the chance of pregnancy is reduced and the deposit is made to a place where life can not occur.

With ‘coitus interruptus’, there is truly no ‘deposit … to a place where life can’ occur! With NFP, the ‘place’ is proper, and the timing makes conception unlikely (just like it’s unlikely for the majority of a woman’s cycle). That’s the difference… :wink:

Can someone help me to understand where the difference lies?

Note that conception doesn’t necessarily always take place immediately at the time of intercourse. Semen may remain in the woman’s body and fertilize an egg that drops within a (relatively short) period of time, up to five days or so following intercourse. The ‘difference’ is that ‘coitus interruptus’ isn’t open to conception under any circumstances, whereas NFP is:wink:

I appreciate the response and thanks for the priestsforlife link… I’ve read all of their work on the topic previously.

Thanks for the response… I appreciate it.

Coitus interruptus reduces the chance of conception, doesn’t eliminate it… I don’t see the distinction between the two. The intention is the same for both.

I think that’s pretty much the standard answer for most questions that start with the word ‘Why’.

One is natural and the other is not.

How so?

oy vey…

The difference is that NFP can also be used to try and get pregnant. Birth control can’t do that. It cannot increase your change of having a baby, but with NFP, you can. NFP is true family planning, because you can gauge when your most likely to get pregnant. The Church teaches too that even with NFP, if you choose to avoid, it must be for a good reason. So, “I just don’t want any more kids” is not a good enough reason, but if you cannot afford another baby, that is a different story.

But the big difference is that birth control messes with your body to avoid getting pregnant. NFP uses your body’s natural elements to gauge when you are most likely to get pregnant and allow you to choose to avoid (with good reason) or pursue pregnancy.

Sex is ordered to be unitive and procreative. If one is missing, it is disordered. Coitus interruptus is not unitive or procreative therefor it is disordered.

If there is an intention to avoid pregnancy, the answer is to avoid having sex at all. NFP should not be considered “Catholic birth control.” Catholics are supposed to be open to life.

But NFP itself avoids being a sin because having procreative sex at any time of the month, including infertile times, is not a sin, and of course it is also not a sin for a couple to agree together that they will not have sex for a period of time, for a serious reason.

It is not only intention that is discerned here. Action takes a critical role.

With NFP, the couple chooses to abstain - not act - during the fertile time if they have reason to avoid pregnancy. There is nothing immoral about that. The couple may also choose to enjoy relations - act - during the non-fertile time. They aren’t doing anything to prevent conception. They just aren’t doing anything at all for a few days per month.

With coitus interruptus, the couple chooses to enjoy relations during the fertile time and further chooses to [attempt to] thwart the life-generating meaning of the act. They are taking 2 actions intended to indulge themselves.

There really is no comparing 2 selfish actions with inaction, even if the agreed upon inaction stems from selfish motivation.

The Church only teaches that the sexual act must be open to the possibility of new life, there’s absolutely no requirement for new life to actually be possible. In other words, the sexual act must do nothing to preclude the possibility of life.

Condoms and birth control change the nature of the sexual act (because they were done specifically for the act), whereas natural infertility has no relationship with the sexual act (and therefore does not close the act to the possibility of life).

Hope this helps!

NFP acknowledges that the male can be considered to be fertile 100% of the time; the female is considered to be fertile during and around ovulation based on several methods of gauging symptoms of ovulation.

Avoiding intercourse during those fertile female times (for individual reasons) takes all of those previous biological facts into account, working with nature for planning or preventing pregnancy. Life and respect are integral to NFP. As mentioned before, the awareness of fertility in NFP is present and, used correctly, can also assist in pregnancy as well.

Practicing withdrawal seems to deny those biological facts and creates a sort of roulette, as do other methods of birth “control”. There is not a solid sense of respect for biology and potential life, just a way to “pull out”. It really is a foolish act. Ineffective. And it is not really cooperative.

I’m sure there are more religious/literary terms for this all; I just prefer to try to bring things to a more conversational level.

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