NFP - can you create your own phase I rules?


My wife and I are going over all of our past charts and now that we want to be more conservative are trying to figure out how we want ot treat the end of Phase I. She has mentruation usually into day 6, and her shortest cycle has been 26 days, so the 21/20 rule would put us at day 6. We have noticed from all of our past charts (8 very good charts, some others that aren’t perfect) that usually we have had relations into day 9 and have been safe.

So we are thinking of creating our own day 8 rule in which Phase II automatically begins on day 9 (granted as long as she is dry). Does this sound reasonable? We have no indication that we are super fertile and aren’t so worried about phase I, but still want to be pretty conservative. I am just wondering how creating your own rules in Phase I is looked upon.

Thanks! God Bless!


I don’t like counting days, personally. It assumes that your body is always going to act exactly the same.

Why not go by the mucous/cervical position signs as the start of phase II???
I thought that’s how most Sympto-Thermal classes taught it?

If you’re fertile… you’ll see fertile signs…
If not… you’re safe!.. right?


Sure, there’s no reason you can’t come up with your own rules based on past experience, but if you’re trying to be conservative it sounds risky.

I do internal observations, and while I often don’t identify mucus outside until day 8 or 9, I can almost always find mucus upon internal observation by day 6. I still have spotting into day 6 and 7, so it’s pretty messy.:rolleyes: That’s just me of course…

If you’re doing internal observations and she’s never identified even the slightest amount of mucus prior to day 8, it might be safe… but I’d rather offer up the extra day or two of abstinence for conditions to change to have another baby.


Sorry, maybe my original post was not clear. We are still checking all mucas signs, and my wife is doing internal checks as well. But if all is dry, then isntead of following the dry day rules, or the 21/20 rule, we would follow an 8 day rule.

Does that make sense? Mucas overrides all rules, so if say on day 6 she found mucas we would start that as Phase II. But again let me reiterate, she is usually into heavy mentruation into day 6 and sometimes day 7 and past charts have shown (8 cycles to date) that her Phase II doesn’t begin until at least day 10.

Sorry, I know this is getting complicated. Anyways thanks for the advice.


In the CCL book there is a rule that does this. I don’t remember the details exactly but it is something like this (WARNING: this is just from my vague memory, please look up the details!):

Take the earliest 1st day of temperature rise in your past 12 cycles or so and subtract 7 days. So, if the earliest 1st day of temp rise is day 16, you should be safe through day 9. This is useful for women who tend to ovulate later in their cycles. Remember you can always add a day or 2 to make it more conservative. Maybe subtract 8 or 9 days instead.

I just remembered…I think this is called the Doering Rule.


I don’t think using phase 1 or 2 would be using conservative rules. I think they are for those who don’t mind a surprise! :wink: When you take a chance in those phases, prenancy rates go up!



Well, certainly phase 2 is out that’s for sure. But phase 1 can be very effective and conservative. Of course nothing is perfect, but I believe some of the phase 1 rules if followed are more than 99% effective.


I don’t know the stats, I’d have to look it up in my book, however, the closer you try to take chances near phase 2 (some women don’t get clear signs every time) then the more likely you get a (happy) surprise! :slight_smile: My understanding (albeit, foggy without looking it up) is that Phase 3 is the most conservative use of NFP–other use is less conservative. Your results may be different :smiley:

More power to you if you don’t adding another blessing to your family :stuck_out_tongue:



I agree, I think if you need to be conservative, you should follow the rules.


Yes there are still Phase I rules that can be considered conservative. Like the clinical experience rules based on the length of your cycle, and we are kind of combining that with our cycle history. THink of it as kind of like a Doering/Day 6/21 day rule!! LOL.

But I am pretty sure that to be conservative you have to COMPLETELY exclude Phase I.


Tally, isn’t your wife only a couple months post-partum? She has to re-establish normal cycles for herself. My fertility care practitioner says I should not rely on what I used to do or be because it could totally change once I start cycling again.


Yes, and I agree with your doctor, I wasn’t asking that question because that’s what we are doing right now. We are just going off of all of our old charts and studying NFP because we didn’t even take a class until we conceived our 2nd child. We were previosuly going off of Taking CHarge of your Fertility which isn’t as accurate or conservative.

So I am not asking this question becuase that’s what we’re doing NOW, I’m asking it because from all of our previous charts that’s what stands out to us. But when her cycles start back up we will definately pay close attention to Phase I and be ULTA-CONSERVATIVE for a few cycles to get back in the swing of things.

Thank you for your concern!


When is her earliest 1st day of temp rise?

We use a made-up day 8 rule as well. Seriously. It’s basically Doering plus an extra day to be safe.


Her earliest day of temp rise has been day 15, so using doering it would put us at day 8 exactly. So maybe by adding an extra day like you did, would put us at a 7 day rule, which would be less conservative than the 6 day rule and more conservative than the doering rule.


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