Ovulation

Ovulation is the release of an egg from an ovary, which happens about 14 days before the next period.

Last reviewed: 2026-10-03

In more detail

The fertile window runs from five days before ovulation to the day after. With a 30-day cycle starting 1 September, the next period is 1 October, ovulation about 17 September and the window 12 to 18 September. Cycles vary, so these are estimates.

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