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28 Day Cycle Overview
Ovulation: Day 14

High Fertility: Day 915 | Next Period: Day 29

Tracking a 28-Day Cycle

For a consistent 28-day cycle, your next period will begin exactly 28 days after the first day of full bleeding from your previous cycle. While apps use averages, your biology dictates that the follicular phase (the days leading up to ovulation) is what causes this specific length.

Your Specific Cycle Metrics

Cycle DayBiological Event
Day 1First day of period (Full Flow)
Day 9 - 15High Fertility Window
Day 14Estimated Ovulation
Day 29Next expected period / Testing Day

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