Device Description : Clue Birth Control is a feature of the Clue period tracker mobile application. C (View more) Clue Birth Control is a feature of the Clue period tracker mobile application. Clue Birth Control’s proprietary algorithm uses period start date information entered by the user to provide predictions of “high risk days” and “low risk days” for becoming pregnant based on a Fertility Awareness Based Method (FABM) of contraception. Identification of high risk days allows the user to determine the days on which her risk of conception is highest, and then make choices about either abstaining from sex or using a barrier method of contraception to prevent pregnancy. To use Clue Birth Control, users go through an onboarding process from within the Clue app, during which they are asked to provide information that will determine whether they meet the Clue Birth Control use criteria. Clue Birth Control can only be used by women who are between 18 and 45 years old and their last 12 cycles were between 20 and 40 days and the difference between the lengths of the shortest and longest cycles is less than or equal to 9 days. In addition, users must have had at least three cycles (four periods) after stopping hormonal birth control (HBC) or since the end of a pregnancy. (View less)