how to figure expected due date
Determining the Estimated Due Date. The estimated due date (EDD or EDC) is the date that spontaneous onset of labor is expected to occur. The due date may be estimated by adding 280 days ( 9 months and 7 days) to the first day of the last menstrual period (LMP). This is the method used by pregnancy wheels.
An easier way in figuring out due dates is to take the first day of your last period, count backward 3 months, add 7 days, and add an entire year. This is called Naegele's Rule. Choose other methods to calculate your due date if you cannot remember the date of your LMP or have irregular periods.