Standard Days Method of NFP


The Standard Days Method (SDM) is a new method of Natural Family Planning developed by the Institute for Reproductive Health at Georgetown University. SDM works for women with menstrual cycles from 26 to 32 days long. To use the method, couples abstain from sexual intercourse on days 8 through 19 of the woman’s menstrual cycle. If a woman has more than one cycle per year that is shorter than 26 days, or longer than 32 days, the method effectiveness decreases significantly and a different method of NFP should be used.


Ahhh, wouldn’t that be to avoid pregnancy?

I like NFP for the fact we are using it to get pregnant, however all I ever see is talk of avoidance.

Avoidance should only happen when there is a grave need to.


a married couple can use NFP to space births if they have a just reason; they don’t need a grave reason to use NFP.


This method would not work for many many women. For someone to have that regular of a cycle with no variation at all is very unusual.
Also, it is not ‘new’ by any means. It’s called the rhythm method, and is why people used to joke “What do you call someone who uses the rhythm method? A parent.”.
It just doesn’t work like one of the methods that actually uses the observable signs and symptoms that a woman’s body sends out. That’s why the newer methods were developed. I wouldn’t recommend this to most people.


Yeah, I’ve heard this “grave reason” talk a lot here on the Catholic forums. Where did people pick up this theological innovation?

Regardless, “Standard Day method” sounds like the rhythm method with some of the insights of NFP. Traditional methods sound more reliable.


Why would I want to abstain that many days (12), when the sympto-thermal method only closes out 5-9 days per cycle (for me)?

What’s the motivation to use something that’s less effective AND less days of intimacy? :shrug:


The “Standard Days” method is not new. It is calendar rhythm repackaged with a new name.

**I would never use this method for any reason. **


**I agree. It is very hurtful to the perception of NFP’s ineffectiveness at preventing conception.

I would never use it either. The other methods make so much more sense for either avoiding or trying to conceive…



I understand that and agree, but by who’s definition? 5 years apart, 10?

I just hope that people don’t use that excuse to the point that are flat out avoiding pregnancy.


**By their definition along with spiritual guidance from a priest and lots of prayer!!!



Standard Days Method is a new method of NFP developed and tested in the late 1990’s. With correct use, its effectiveness is about 95%. Most women have no more than one cycle per year shorter than 26 days or longer than 32 days, so most women can use the method.

The TwoDay Method is another new method of NFP, which can be used by women of any cycle length. Also developed at Georgetown University, its correct use effectiveness is about 96%.

These methods have the advantage of being easy to learn.


Spacing births means decreasing the chance of pregnancy, but not attempting to decrease it to near zero. It does not refer to attempting complete control over how many children are conceived and exactly how far apart. Trying to get complete control over procreation is a contraceptive mentality and is immoral.


NFP, by it’s very teaching, is a conversation with God…
If we’re discussing NFP in the light of the Catholic faith, let’s assume we’re not leaving God out of the conversation… sort of as a basis for this thread.

Regardless… the Standard Days Method is ineffective and allows for LESS intimate days than other methods…

Using a more accurate method does not imply a “contraceptive mindset”… it’s STILL NFP… still a conversation that MUST include GOD.


But it does seem easier.:smiley: lol I was thinking about it today, and thought…wow, this practice would be easy to get. I don’t know if we (my dh and me) want to be bogged down with temperature and mucus methods–is that necessary to follow NFP? (We had our son following the above method (SDM), but I don’t think we were fully understanding it):blush:


The Standard Days Method has been proven by scientific studies done by the Institute for Reproductive Health at Georgetown University to be 95% effective.

Likewise, the Twodays Method is proven 96% effective.

It is true that the number of days for refraining from marital relations, when one wishes to reduce the possibility of conception, is greater (12 days for the Standard Days Method, and an average of 10 days for the Twodays Method). But these methods are very easy to learn and can be taught to a large number of persons very quickly.

There are a number of good NFP methods. Couples can choose which method is most fitting to their lives. As Catholics, we should be supportive of every good method of NFP.


I really appreciate your link, because the site is chock full of information, and different methods and explanations of what might fit a couple’s planning best. Thanks for bringing this to my attention!


95% is very low effectiveness rate for method effectiveness.

And, even when one has a cycle that falls within the range you state, one can still have fertile days outside the 8-19 day range you posted.

If one is serious about avoiding pregnancy, this is not the method to use.

Why are pushing two methods with inferior levels of effectiveness? Sympto-Thermal, Creighton, Billings, Marquette, and NW Family Services have much higher effectiveness.

And the disadvantage of being inferior to the other methods, which are also very easy to learn.


Those of us trained in NFP do not consider either of these methods to be “good” methods of NFP or worthy of support.


This is a nonsensical statement.

The Church clearly teaches that one may space or postpone indefinitely when one has a just reason. There are many women with serious medical conditions or other just reasons that require them to avoid children completely until menopause.

This is in no way immoral


1757 The object, the intention, and the circumstances make up the three “sources” of the morality of human acts.

For an act to be good, all three must be good. So if one uses NFP, which is moral, but with an immoral intention, then it is still a sin. The contraceptive mentality, in which a person or a couple attempts to do only their own will concerning procreation, thwarting in any way the will of God in procreation, is a sin.

If a couple has a grave reason, they can use NFP with the intent of avoiding all conception, since they discern, by means of the moral law, the will of God to that end. But they must still accept whatever Providence gives them in that regard.

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