TRACKING OVULATION USING OPK!!!!! This was a video I made explaining how to track ovulation using an ovulation test strip. If you look at cycle day 15, you can see that the test line is even darker than the control line indicating peak ovulation. For an ovulation test to be positive , the test line must be darker than the control line unlike pregnancy test which is positive even if the test line is not dark. Ovulation occurs 24hrs to 36hrs after a positive ovulation test kit. Also it is better t