First, there are several kinds of NFP.
You need to examine why it “didn’t work.”
For several months now, my wife and I have been using LH test strips: both the really cheap kind and the expensive ClearPlan that’s used in the Marquette Model, along with checking cervical mucus and cervical position.
We’ve gotten to where a day comes when there’s a really dark purple line on the disposable test and the ClearPlan shows a little ovulation day symbol, and the cervix is unreachable and there’s globs of mucus and she feels a pain in her abdomen. And we know she’s ovulated.
Sympto-Thermal NFP requires a bunch of stuff that really doesn’t work once you have kids, unless a) you have perfect health and b) you’re super-organized in your life.
And breastfeeding, while it extends amennorhea, can also fool the body so that many methods of NFP don’t work when a woman is breastfeeding.
Add to that any health issues.
So we’ve been trying different supplements for months now to try and improve my wife’s health. The NaPro Technology people (a subset of Creighton Method) suggest progesterone supplements for women who have “double peak” or other irregularities in Phase II & Phase III, because progesterone is the hormone that, when everything else is done, tells the body to release the egg.
Usually, what’s happened with us is that we see all the signs of a “Peak Day”, but ovulation doesn’t occur. A few days later, when we think we’re in “safe time,” according to the books, she ovulates. This is one variation of a common phenomenon called “Double peak,” that most NFP books only treat as a rare footnote.
For the last 3 cycles, she’s used progesterone supplements. When she gets an apparent “Peak Day,” she waits a day or two. If there’s no indication of ovulation (e.g., the sharp pain in her side), she uses the progesterone cream. She practically ovulates as soon as she uses it.
(Note that one must be very careful with the progesterone timing to avoid using it as a contraceptive).
I also discovered a supplement called Goat’s Rue: it’s the herb from which the diabetes medicine Metformin is derived, and it’s been used by herbalists to treat diabetes for centuries. Metformin is also used to treat PCOS. Goat’s Rue is usually promoted as a supplement for nursing mothers. My wife’s family have a big history of diabetes and PCOS ,and she has many symptoms of both. She’s been taking the Goat’s Rue for a month and a half now, and her cycles have been
The Goat’s Rue has improved her overall health and her cycles, as well. The last two cycles have practically been “by the book,” “Rhythm” Cycles.
It’s taken us 8 years to figure out NFP, but we finally did after several “accidents” that we now can’t live without. Our experience is that, if you’re struggling figuring out NFP, keep trying your best. If you really can’t get it to “work” after studying, praying, and trying everything you can to do it, then God wants you to have another child, and He will guide you to the knowledge of NFP when He wants you to have it.