Cycle & ovulationDraft: awaiting clinical review

Ovulation

The release of an egg from the ovary, and the signs that can help you recognise it.

Overview

Ovulation usually happens once per cycle. The fertile window is the few days leading up to and including ovulation, because sperm can survive for several days.

Signs include clearer, stretchy ('egg-white') cervical mucus, a positive LH test, and a small rise in basal body temperature after ovulation.

What is well established

Regular cycles between 21 and 35 days usually indicate that ovulation is happening.
A rise in basal body temperature only confirms ovulation after it has happened.
Calendar or app predictions are estimates and can be inaccurate, especially when cycles vary.

Uncertain or emerging evidence

Wearable devices and apps that claim to predict ovulation vary considerably in accuracy, and few have been independently validated.

This guide is general information and does not replace advice about your own circumstances. Clinical review pending.