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Ovulation typically occurs 14 days before your next period. With a 28-day cycle, that's day 14. The fertile window spans 5 days before ovulation through the day of ovulation, as sperm can survive up to 5 days.
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How many days is the fertile window?
The fertile window is about 6 days: the 5 days leading up to ovulation plus ovulation day itself. Eggs survive 12–24 hours after release.
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