How do I determine day 1 of my cycle? Hertility Support Team August 20, 2021 14:12 Updated Day 1 of your cycle is your first day of full bleeding before 5 pm. Related articles How to take the test? What does the Hertility journey look like? Who should take the test? Will my results be inaccurate if I collect my sample incorrectly? Will a doctor review my results? Comments 0 comments Please sign in to leave a comment.