The first thing to remember when trying to work out your due date is that less than 5% of babies will actually be born on this date. Up to 50% of babies will be born within 1 week of their due date. So by all means, go ahead and work out your “date” but maybe also consider calling it your “birth month”. This may save you a lot of stress and anxiety if you go past full term! Keep in mind that once you have your prenatal ultrasounds, your due date may change depending on the size and growth of the baby.