How Accurate Is The Due Date Your Doctor Gives You?

The fact of the matter is, very few woman actually deliver on their due date.  A normal pregnancy lasts anywhere from 37 to 42 weeks.  4% of babies are born on their due date, 6-10% of babies are born early and 4-14% of babies are born after 42 weeks.

Your due date is figured by the first day of last menstrual period (LMP).  Add 280 days (40 weeks) to your LMP and you will have your due date.  This assumes that you have a period every 28 days, but if you have a longer cycle than you are likely to deliver after your due date and if your cycle is shorter you may expect to deliver earlier.

The most accurate way to figure your baby’s due date is by ultrasound during your first trimester.  During this ultrasound the technician will measure the size of the baby and your doctor may adjust your due date if the measurements don’t match up with your LMP.

Even with an exact date of your LMP or with an ultrasound you may not deliver your baby on its due date because no one is exactly sure what triggers labor.  Typically, when you reach 40 weeks your doctor will begin weekly or bi-weekly stress tests to make sure that your baby is still safe in the womb.  If it is determined that your baby could be in distress, or if there are other problems your doctor may induce your labor.

Try not to get frustrated if you go past your due date.  Try reading a good book, or working on a fun project to pass the time and soon you’ll be smiling at your new bundle of joy.


How Accurate Is The Due Date Your Doctor Gives You?