i tried opk one month, and gave up. the next month all i did was input my cycle/af info in a ovulation calculator thing, and it told me which days i was fertile. we bd those 4 days, and i got pg. (that was my last pg and m/c). but i think that verrrrry scientific method only works if your cycles are very regular. it was just annoying trying to decipher the darkness of the lines (opk) and then i read also that sometimes you get your lh surge later in the day. so if you tested in the morning, the line might not be pos., but then later in the day you get your surge, and it goes down by the next day when you test again. so you can totally miss it unless you are testing 2-3 xs a day. could be the ic just aren't great, but i always heard that ic hpt were great. not sure if that applies to opk too. good luck though! just bd as much as possible