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21 Day Cycle Overview
Ovulation: Day 7

High Fertility: Day 28 | Next Period: Day 22

When to Test for Pregnancy

Implantation typically happens 6-12 days past ovulation. If you have a 21-day cycle, testing before Day 20 might yield a false negative because hCG hormone levels haven't concentrated enough in your urine. The most accurate time to test is on Day 22 (the day of your missed period).

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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