My cycle is usually 30 days long so according to the little table in the instructions I should start using the OPKs around CD14, but I'm wondering whether it might pay to do it sooner anyway, just to be sure...!
Also, i think i remember reading somewhere that 2pm was the best time to do them? What time have you got a +ve OPK results? Would it be beneficial to test twice a day?
I'm only so paranoid because I've only used OPKs for 2 previous cycles and neither time did they detect O.
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