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Ovulation Calculator

If you would like to calculate the days when you are most likely to become pregnant, please enter the first day of your last period into the calculator below. You are most likely to become pregnant if sexual activity occurs right before or after ovulation.

Your date of ovulation is calculated by subtracting 14 to 16 days from the date of your next period. This is an approximation and may not be exact for every woman. These calculations may not be accurate if your cycle is less than 21 days long or more than 35 days long, or if your menstrual cycle is irregular from month to month. Please consult your doctor for more detailed information.

Enter the first day of your last period:

Month:

Day:

Year:

Enter the number of days in your menstrual cycle.
(To determine the number of days in your cycle, count the days beginning with the first day of your last menstrual period (first day of bleeding) up to and including the day before your next period.)

Current as of June 2007

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