The femSense algorithms determine your fertile days and the correct patch application day based on previous cycle lengths. The sensor patch should be worn during your fertile days in order to measure and confirm ovulation. However, if you think that the patch application day has not been optimally predicted for your cycle please get in touch with our support: email@example.com. They will be happy to help you out and can adapt your current cycle calendar if necessary.
For Fertility Awareness Method experts: If you know that your luteal phase is definitely shorter or longer than femSense has estimated, you can change the estimation by changing the luteal phase length under Menu --> "My Body". This action will alter the predicted patch application date as well as the fertile days. This feature is intended only for users who are confident that they know their luteal phase length. If you are unsure, please contact our support team prior to altering femSense's prediction.