How effective is NFP?


Hi! I did a search on this topic, but couldn’t find one, so I thought I’d start a new thread on this. Did anyone know how effective NFP is? I’ve read CCC on this, but it didn’t mention effectiveness. I looked on Wikipedia, but ended up being more confused than before I read their entry. Anyone have insight on this? Maybe reading Theology of the Body may help? Thanks in advance!


There don’t seem to be many scientifically sound statistics on this. Many sources lump NFP in with other methods (e.g. rhythm method) making NFP appear less effective than it is. Some NFP promoters claim it’s more than 99% effective, but that number doesn’t seem to come from well-conducted, scientific study.


There are various methods of practicing NFP. All are extremely effective when practiced correctly. Look at the Couple to Couple League website to find out more.


These are the published studies for FertilityCare (Creighton).


This is true of almost all secular sites that have “contraception” effectiveness statistics-- such as CDC, FDA, WHO, etc.

Actually, this is totally incorrect. There have been numerous scientific & peer reviewed studies specifically on STM, Creighton, and Billings.


Is anyone else bothered that the assumption when someone asks about the effectiveness of NFP is to prevent conception?

NFP is Natural Family Planning. It is more than preventing pregnancy. It is all about both partners being actively involved in understanding, celebrating and stewarding the gift of fertility.

When Catholics speak of NFP as if it is another form of birth control, it reinforces that type of mindset. When I hear of Catholics bragging about how it is MORE EFFECTIVE than other types of contraception…I cringe. Because so much effort has gone into getting it into people’s head that NFP is not just another form of contraception.

Words are powerful. Most people think in verbal terms, and the words they use in their heads mold their ideas about things.

NFP is a terrifically effective way of staying aware of a woman’s fertility. What is done with that knowledge is between the couple and God.

Please don’t fall into the trap of discussing NFP as if it is another form of contraception. Talk about how effective it is in predicting fertility.


Thank you all for the info! It’s much appreciated.


Another thing to remember about NFP is that people who use NFP are usually more open to life than those who don’t. So, I have read about stories of couples who kind of risk it on semi-possibly-fertile days, and end up pregnant when there were technically avoiding, but in the end didn’t mind, because that’s the point of NFP, to be open to life. So it might seem to be less effective than contraceptives in preventing pregnancy because of them. Another advantage is that, unless something REALLY screwy is going on with the woman’s body, or you’re not interpreting the signs right, you’ll KNOW if you risked it. Whereas with, say, the pill, you have NO IDEA if you had a breakthrough ovulation. And suddenly, you’re shocked because you got pregnant when it was ‘impossible’. So at least with NFP, you know what’s going on with your body.


True. But…

If NFP were not effective as a birth control method, I would be abstaining forever. :o I have been told, many times, that I should not get pregnant again. So, if people only talked about how effective it is in predicting fertility, but never said anything about birth control, I wonder how long it would have taken me to trust NFP.


I can appreciate what you wrote here. That is exactly the reason I gave the statistics for achieving as well as avoiding pregnancy. The OP didn’t ask specifically for either one.


NFP can be used to avoid pregnancy when there is serious reason to do so. Here is a news link about NFP.


Hi everyone,

My wife and I have been married for almost six years. She was on the Pill for 1 year and then we decided to have a baby. We were blessed with a daughter. Then we used barrier forms of birth control for one year. Then we had our second child. Since then (2 years ago) we’ve used barrier methods of birth control.

I’ve never been that comfortable using barrier mehods of birth control. In March of this year after listening to some lectures by Archbishop Fulton Sheen and after reading articles on the negative effects of birth control I told my wife that I wished to embrace natural family planning. She was very upset. She felt that I was trying to force her to have another baby. She says she’s not emotionally ready for it. I spoke to a S.J. priest about it and he said that we should continue doing what we’ve been doing, pray for each other and meet weekly to discuss it. Well we didn’t follow his instructions very well. I have grown resentful of this compromise and so a few weeks ago declared that I no longer wanted to use the barrier method of birth control. We ordered a machine that aids with identifying her various cycles.

We are both at odds over this and it is extremely challenging to feel like the enemy when I only wish to do what is and feels right. My question to the forum is how does one convince a spouse as to the benefits of NFP? Will it become self-evident once we start using it/if we start using it???

Thanks NFP2007


First of all you need to take a class in NFP. They will go over the benefits and effectiveness -along with the church teaching on Natural Family Planning. If you try to wing this on your own without real knowledge and your wife becomes pregnant unexpectedly she will come even more resistant to the idea. I would not put my entire trust in a machine. Secondly show her the article that I posted a link to. Since it comes from a secular source she may be more convince because some believe the church exaggerates the effectiveness of NFP.

I have used NFP for 10 years to avoid pregnancy because I have a life threatening heart condition. We do have one daughter who is now 11 which we had no problem conceiving so I know I have no preoblems with fertility. NFP does work but you must have the proper instruction on how to use it in order for it to be effective.

I would check the Couple to Couple League for classes in your area.


This is one of my favorite studies about Creighton. It takes into account that NFP can be used for both achieving and avoiding pregnancy. It looked at the subject’s charts and if there was a pregnancy it categorized it into a few categories: achieving related behavior (people having sex at a time when they knew they were fertile whether or not they were “taking a risk” or not), teacher error, subject error, and unexplained pregnancy. The only subject that had a pregnancy which was “unexplaineable” based on her chart was a woman who just got off the pill.

The method related preganancy was 0.14%, teacher error or subject error related pregnancy was 2.72% (meaning someone goofed but upon review the goof was an error in understanding how to use the system), and achieving related behavior pregnancy rate (having sex during fertile time) was 12.84.

The article concludes that CrNFP is just as good as other methods of artificial birth control.


Just a slightly off topic note…Wikipedia is a highly unreliable and unreputable site for facts…


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