Midwife Nikki replies:

No, unfortunately not. But you may be comforted to know that only 5% of babies actually arrive when they're supposed to.
Your due date is just a guide to when your baby is likely to be born, so it's called an ‘estimated due date' or EDD.
Many women go into labour from 37 weeks onwards, and about 40% of babies arrive a week after their due date.
So have your bags packed from 37 weeks, and you may well get to eat your Christmas dinner at home.