Overview

You can most accurately pinpoint your ovulation day by monitoring your cervical mucus, your basal body temperature (BBT), and your luteinizing hormone (LH) changes.

• During the 5 to 6 days before and on the day of ovulation, the cervix produces a type of mucus that is stretchy, slippery, thin, and clear. This quickly changes on the day after ovulation.
• About 24 hours before you ovulate, your LH level rises. You can confirm that ovulation is approaching by testing your urine for high LH with a home ovulation test. Note that an LH surge can happen as close as 16 hours or as far as 48 hours before ovulation.
• Just before your ovary releases an egg (ovulation), your BBT dips slightly. Then, 24 hours after the egg's release, your temperature rises sharply and stays up for several days. Before ovulation, a woman's BBT averages between 97°F (36.1°C) and 97.5°F (36.4°C). After ovulation, it rises to 97.6°F (36.4°C) to 98.6°F (37°C). After 2 to 3 months of carefully measuring and recording your BBT every morning before getting out of bed, you may be able to identify a pattern that helps estimate when you are ovulating.

If you have unusually long or short menstrual cycles of less than 21 days or more than 42 days, monitoring your cervical mucus is your best bet for identifying your ovulation day. A home ovulation LH test won't work well for you.