Calculating one’s due date gives you the approximate expected date, but in reality, your doctor might not be arriving at the precise date because he or she has no idea of the time of conception. This could make the pregnancy math a little tricky. But the thrumb-rule doctors have of calculating this is by knowing your last menstrual cycle. Officially, they count the 40 weeks of pregnancy from the last period. Your pregnancy tracking records are marked with the due date and you could mark the same in your calendar and begin the countdown. Unless a pregnancy happens through the IVF-method, a doctor would not be able to decide upon the exact due date. Moreover, quite a few times your due date is revisited and change by plus or minus days. Why does this happen? Let’s find out:
If You Have Irregular Periods:
For women with irregular periods, it can be a difficult task to gauge the exact due date as the irregular cycles can’t help you pinpoint. This is why an ultrasound exam is what such women need to determine the gestational age. In quite a few pregnancies, it is not an ultrasound, but a Doppler heartbeat that is used to assess the state of pregnancy. If you had one of the Doppler check-ups, it’s likely that your doctor’s calculation of your due date has vastly varied from what it is. Having said that, if you had an ultrasound, but your due date has been bigger than the seven days away from the due date calculated by your last periods, your doctor will then go by the date as arrived at by the ultrasound. But if the difference between the ultrasound due date and the date calculated from the last period is less than a week, your doctor would go by the latter.
When Your First Ultrasound Is Performed In The Second Trimester:
This is one of the reasons why your due date has a shift. The ultrasounds done in the second trimesters don’t always come precisely. According to the American Journal of Obstetrics and Gynecology, the nearest possible due date comes from ultrasound tests taken in the first trimester. So you might want to get an ultrasound done in the first trimester for sure.
When Your Fundal Height Is More Than Average:
The fundal measurement, which is the distance from the top of the pubic bone to the top of your uterus, is taken as an equivalent size of your uterus. So if your healthcare provider takes these measurements, don’t be alarmed. In fact, the fundal height is said to correspond closely with how far in pregnancy you have come. You are estimated to measure big if the size of the uterus does not align with the standard growth charts. You might have your due date moved if your healthcare provider assesses that your measurements are off by three weeks or more.
The Abnormal AFP Levels:
Alpha-fetoprotein or the protein that is usually produced by the liver and yolk sac of your developing fetus might also determine the due date given to you. Between the 14th and 22nd weeks of your pregnancy, you might be advised to go in for an AFP screening. The AFP levels vary to quite a good degree throughout your pregnancy and are often assessed through a triple screen. If the AFP levels are high, it might mean that there is a potential genetic abnormality. However, in most cases, the AFP levels are high because the due date was simply miscalculated!
The whole scenario suggests that despite medical advancement, your due date might not be precisely calculated, be it through traditional or modern methods. The other thing you might want to bear in mind is not to get carried away or get anxious if your due date has been moved much before than expected. Trust us, it might be a good idea to have a second opinion in such cases. The longer the baby can gestate in the mother’s womb, the better it is for its growth. You do not want to be rushed into a C-section simply because a doctor miscalculated your due date! One could wait for up to 42 weeks to give birth! It isn’t too long when compared to the many weeks spent growing the little angels inside you already!