I had to use temperature and cervical position & mucous pretty much without the other little formulae. It actually worked very well, except for last month when my chart was all wacky and I subverted it.

Anyway, we would consider day one safe, and then every day until the first change in mucous (usually from dry/sticky to creamy). The first creamy day was the last day we were "safe" and after that I'd use temperatures & position exclusively (because I often had fertile-looking mucous long after I ovulated). I invariably had a temperature dip when I ovulated (I know that not everyone does) followed by a sustained rise in temperature. We waited two or three days after the dip and after that we figured we were infertile again. And up until last month, it worked well. Last month my chart was whacky, but I had a dip and then two higher temperatures and thought that we were fine. On the third day, I had that super low dip and that's when I realized that we were pregnant.

In other words, I didn't pay attention to my own rules as well as I should have, probably because I've got serious baby lust.
The rules you listed make perfect sense, if you don't have short cycles. This year my cycles have been longer (26-32 days) but earlier (when we were TTC BooBah) my cycles were very short, 18-22 days. In fact, when we started TTC BooBah, we missed several fertile cycles because I was counting days instead of taking temperatures or checking mucous. I was ovulating as early as day 5, usually between 5 and 10. I didn't think that my cycles were that abnormal, though, I thought that other people had really short cycles sometimes...

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