With an ovulation calendar or an ovulation test. The former allows you to find out the expected day of ovulation as long as you know the precise date of the latest menstrual cycle and the normal length of your cycles. Ovulation takes place halfway through the menstrual cycle, which means it occurs on the 14th day if it is a regular, 28-day cycle.
Ovulations tests measure a woman's LH (luteinizing hormone) levels when she is ovulating, as a surge occurs during this phase of the cycle.
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