"Just add 7 days to the date of the first day of your last menstrual period (LMP) and count back 3 months." Example: If your LMP is January 16, then your EDD is October 23. How to compute? Month: January minus 3 months equals October. Day: 16 plus 7 equals 23. Remember: These dates are not 100% accurate. Your baby may arrive two weeks earlier or later than the EDD. Return to pregnancy and prenatal check-ups … [Read more...] about Learn how to compute for the expected date of delivery (EDD)