Before ultrasound was in regular use the due date was determined by when you had your last period. The method was very accurate, except when a woman did not know when she had her last period, or had irregular periods. Of my four children, three were born exactly on their due dates/
Hi and thanks for using the forum.
Usually, the first due date that your doctors give you is the most accurate. Since every womans cycle is different, this due date is an estimate- it is not exact. Sometimes, based on an ultrasound, doctors may change your EDD, but again, this is just an estimate. If you are fairly accurate with your dates, then you can rest assured that your estimated due date is fairly close. Good luck and congratulations on your pregnancy.
Bridget