So to get myself to feeling more positive about this cycle i've decided to bite the bullet and just ordered myself some OPK's for the first time. Never used them before, Never even READ too much about them before, But i want to know that i AM BDing on the right days of the month and not just missing it completely and then getting downhearted for no reason you know?? They should be delivered on 2nd Feb so by then i'll be on CD5. I have a few questions.. I know that the OPK's go by the surge of 'leheal' (oh god how embarasssing i cant remember how to spell it but you all know what i mean!) that is the hormone which is detected when ovulation is to occur 12-36 hours later .. so my questions.. When should i begin using the OPK's? On what cycle day? ive heard CD10? Will the difference in the control line and the other line be a BIG difference? will it be really noticeable? when is the best time of day to take them? ANY other info would be really appreciated ladies! Sorry im a newbie to them!