Hi ladies! This was my first month using OPKs. I used the generic two line tests every day--twice a day!--starting on CD6. I know that's early, but I had a chemical pregnancy last month and was worried my cycle might be wonky. I didn't want to miss the surge since my husband and I wanted to try again this month. Anyway, I didn't get a strong positive until CD18 (last Saturday, see below). I also did the ClearBlue Digital OPK and I got a smiley face!! My husband and I were super excited so we BD'd twice that day, as well as the next day (Sunday, CD19). I assumed that, in addition to all the BD'ing we'd already been doing in the runup, that would be enough.