This is the first month I have tried charting BBT. Before I more or less relied on OPK's, so when I saw a positive one, I would keep on testing for another few days until the OPK was negative. Needless to say we would then BD like billio, then after that, take a bit of a BD break. So this time round I am charting, and OPK'ing as well. Early last week I had positive OPKs for 2 days in a row, but my charting did not indicate that I was ovulating. It is only in the past few days that my charts show that I have just O'd. I know from the Toni W book that the OPK's aren't always reliable, and your body can gear up to O but not actually O when you think you will. I suppose what I'm trying to say in a long winded way is in the future I am not going to rely on the OPKs as I have been doing because (for me anyway) they are not reliable! Am hoping this is what I've been doing wrong since I've started TTC!