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21 Day Cycle Overview
Ovulation: Day 7

High Fertility: Day 28 | Next Period: Day 22

Your Fertile Window Explained

Because the luteal phase (post-ovulation) is almost always 14 days, a 21-day cycle means you ovulate around Day 7. Sperm can survive up to 5 days internally, meaning your highest chances of conception fall exactly between Day 2 and Day 8.

Your Specific Cycle Metrics

Cycle DayBiological Event
Day 1First day of period (Full Flow)
Day 2 - 8High Fertility Window
Day 7Estimated Ovulation
Day 22Next expected period / Testing Day

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