Since only 5% of women go into labor when they expect, it’s quite likely that you know someone whose due date has appeared to fail them. You see, due dates are not necessarily meant to tell you the day your baby will arrive (though that seems most ideal), but rather are in place for another, very important reason: to help physicians give you the best prenatal care possible.
Though the science of due dates is not as exact as we may like, due dates are essential for doctors to accurately track maternal health and fetal development. As your doctor tracks the development of your baby, having an estimated due date will help him or her decide when to implement certain tests and other steps of prenatal care.
Although it may be comforting to know the essential role of due dates is fulfilled whether or not your baby arrives on said day, it can still be a source of stress for mothers-to-be as they anxiously await the arrival of their unborn child. You may be left wondering, “Why is the exact day so hard to pin down?”
Due dates are calculated based off of your last menstrual period, meaning your doctor will add 280 days (40 weeks) from the day of your last period in order to establish a due date. However, the reason this is not always 100% accurate is because of the uniqueness of your genes. There is only one of you and one of your spouse, so the way your baby develops will also be unique. One way genetics can influence a baby’s expected arrival is if you or your spouse were born prior to your due dates. If so, then there is a chance your baby will also come early, due to the fact that you have faster-growing genes at work, which may potentially trigger labor sooner. Furthermore, your height may have an impact on when you go into labor due to the fact that short women (less than 5’3”) typically deliver babies five days earlier than taller women (5’6” and above). These are just a couple of ways genetics can influence your the exactness of your due date.
The most common way that due dates are confirmed is via ultrasound. Most OB doctors try to do an ultrasound in the first trimester. First trimester ultrasounds are the most accurate way to date your pregnancy.
Ultimately, it is important to keep in mind that due dates serve a clinical purpose and allow the doctor to interfere when necessary, speed things along, and deliver the baby in a timely manner. Though the anticipation may be frustrating, you can rest assured knowing that the due date has served its purpose in helping your baby grow strong and healthy.
To learn more about why your due date is important, please check out the article below: