Estimated Date of Conception

Why an Accurate Estimated Date of Conception Is Important

It’s important that your prenatal health care provider estimates your conception date as accurately as possible. The following are good reasons why estimating conception date accurately matters.

Your conception date predicts your expected baby delivery date. This is huge for many reasons:

• It allows you and your health care provider to know if you’re overdue or going into labor too early.
• It provides a timeline of expected prenatal appointments and pregnancy symptoms and allows your health care provider to note if something is amiss. For example, your provider can’t know that your baby seems small at the 20th week appointment if no one is sure what week you’re really in.
• If you’ve had problems with previous pregnancies, your conception date can provide useful information. If you’ve had miscarriages only before the 10th week, you’ll likely feel some stress reduction once you hit that 11th week mark.
• You get to plan ahead for the arrival of your baby. Now you know how long until that nursery needs to be decorated!

Other important reasons for an accurate estimated date of conception include:

• If your choice is to terminate a pregnancy, you need to do it within a specific safe timeframe.
• You can possibly tell who the father is if you happen to have more than one sexual partner.

Your Conception Date Is Just an Estimate

What’s important to know is that as few as five percent (at most ten percent) of babies are born on their due date. This is because all your health care provider can give you is an estimated conception date. No one can tell you exactly when you’ll go into labor or give birth.

Additionally, almost all health care providers add on an extra two weeks to your due date. In a normal 28 day cycle, ovulation usually occurs midway between two menstrual cycles, so two weeks are tacked onto your conception date. This is why you may hear your delivery date called your “Expected date of delivery” (EDD) – labor and birth is expected to happen around the due date time but not right on the due date. The downside is that not all women have regular 28 day cycles or some just don’t ovulate at exactly midway between periods so these two weeks can be completely arbitrary.

If you do give birth naturally on your EDD, it’s chance, not the prenatal provider’s knowledge, that explains it.

Estimating Conception Date

To get the most accurate estimated date of conception, your health care provider will ask you when the first day of your last period was. If you don’t know, they’ll ask you to guess. If you become pregnant and you’ve always had a very irregular cycle, or you just quit taking the pill, then your conception date may be hard to estimate.

Besides cycle dates, there are a couple of other ways to estimate your conception date. As your belly starts to grow, a general conception and due date can be estimated due to your belly measurements. Of course, belly measurements are somewhat flawed because some women gain weight faster or pop out quicker than others.

Sometimes, you can also guess at conception due to pregnancy symptoms especially if you happen to catch some of the earliest signs of pregnancy. For women who are unsure of their conception date due to cycle issues, early ultrasounds can be used but usually not before eight weeks.

Try Not To Worry

Not knowing a confirmed due date until eight weeks is not as bad as you might think. Sure, an accurate conception date is important, but if you have a confirmed clinic or home pregnancy test, then you can still have a healthy pregnancy even without knowing the exact conception or due-date. Being pregnant is the same either way.

You’ll want to follow your prenatal health care provider’s advice for a healthy pregnancy. You’ll also need to start learning about proper pregnancy exercise and pregnancy diet guidelines as well as give up any bad habits such as smoking. This way, even if you don’t learn your EDD until your first early ultrasound, you’re still helping to ensure the healthiest possible pregnancy.