Determine the length of your menstrual cycle before the test (The length of the menstrual cycle is the duration from your first menstrual bleeding day to the day before the next bleeding begins). Please refer to the cycle chart on the picture to determine when you should start testing. If you do not know your cycle length, you may begin the test 11 days after your first period since the average cycle length is 28 days.
Example: If your cycle length is normally 26 days,the chart indicates testing should begin on day 10.
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