Update your menstrual cycle information. See Editing Menstrual Cycle Data for more details.
Choose the option "Avoid Pregnancy" in the I want to achieveOptions area.

You can select Precise Calendar or Fixed Days calendar methods.
After you complete the steps described above, Your Days ovulation calendar calculates the unsafe days:

The unsafe days are marked with 'stop signs'. To avoid an unwanted pregnancy, abstain from unprotected sexual intercourse during these unsafe days. The most fertile day is the day of ovulation. The day of ovulation is marked with a light-green and italic number. See Ovulation and Contraception for more details.
To ensure that the calendar is correct, you need to keep your menstrual cycle information up to date. Your Days ovulation calendar will alert you when this information becomes outdated. To update it, click the link Update Days in Options area. See Keeping the Calendar Accurate for more details.
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