OVULATION CALCULATOR
Author: http://calcnexus.com
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Your ovulation date is normally 14 days before the start of your next period. If you have a regular menstrual cycle, you start with the first day of your last period and add the number of days in your average cycle and then subtract 14. This calculator also estimates the dates for the range of fertility, based on subtracting 2 days and adding 3 days to the ovulation date.