To determine the best day to start testing you should know the approximate length of your menstrual cycle. If you do not know, it is recommended you wait for at least one menstrual cycle before testing with Early Bird Swift ovulation tests, so that you can determine its length. Day 1 is the first day of bleeding. Carry on counting until the day before your next cycle starts. This is the length of your cycle.
Use our Ovulation calculator below to see when is the best time to start testing