When in my cycle it’s best to use Diagnio?The best time to use the Diagnio Kit in the first month is during the period from the 10th to 20th day of your cycle. Starting the next month, you can shorten the testing window down to 6 days (from the 12th-18th day of your cycle). Good news! Our App is AI-powered. The more cycles you test, the better it will learn your personalized pattern and further advise on when to test next.