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21 Day Cycle Overview
Ovulation: Day 7

High Fertility: Day 28 | Next Period: Day 22

Phase Breakdown & Health

A 21-day cycle is composed of two main halves. The first is your Follicular Phase (lasting roughly 7 days). The second is your Luteal Phase, which is structurally fixed at around 14 days. If you recently stopped hormonal birth control, expect it to take 3-6 months for your natural 21-day rhythm to fully stabilize.

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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