BBT vs. OPK - what to follow?

[LCJar]

Hi all, first time poster in first month of TTC.

Have used Natural Cycles since April 2023 to prevent pregnancy and have always been pretty good at tracking BBT. Period predictions usually pretty accurate. Cycles range from 30-32 days.

This month I got a peak OPK on CD 18, remaining high on CD 19. DTD CD 14, 18, 19. NC said O would be day 19, and had negative OPKs since.

NC has just this morning confirmed ovulation on CD 23. This is a bit annoying and haven’t DTD since CD19 and means that the whole fertile window has changed.

Is it possible that my temperature wouldn’t rise immediately after O? And that the peak LH test would happen 5 days before ovulation? It does seem to dip before what I thought was O.

New at this so just looking for advice! Thanks in advance.

Judging by your chart I think NC is right and you ovulated when it said you did. I never found ovulation tests hugely reliable personally.

Oh, and as an aside, I would move to testing your BBT vaginally as it tends to be more accurate and consistent than oral.