Question about Peak day


I am a user of the Creighton model of NFP and have been using the method for going on three years. I was wondering if anyone could explain to me what is the Peak day in relation to ovulation? I understand the whole definition (last day of peak-type mucus- mucus that's clear/stretchy/lubricative) but I would like to know how it relates to when you ovulate. Is the peak day the day you ovulate generally, or can it happen anywhere within the plus or minus two to three days of it?

While on the topic, I've often wondered if there is an average length of time that the buildup to peak lasts. I haven't had a whole lot of time having normal cycles as I have been pregnant or breastfeeding for the majority of time that I've been using NFP, so for me sometimes I have had just one day of peak type mucus and other times it is five or six days. Is it generally a pretty set number of days for the woman, or can it vary within a woman each cycle?

Any insight would be awesome! Thanks.


It's been a long time since I had to worry about this and I imagine there has been more study data since then but from what I remember...

The peak day is likely to be either the day of ovulation or the day before ovulation. One of the reasons you wait a few days after the peak day (if you are trying to avoid) is to make certain ovulation has had a chance to occur. It's not just because ovulation was delayed or because you might ovulate multiple times.

I'm sure there is a typical build up time but it certainly didn't happen in my case. So I'll let someone else answer that part of your question.


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