What is a Viability Scan?
Congratulations, you’re expecting! The Viability Scan is the first scan in your pregnancy journey. It is sometimes referred to as the “dating scan”, however our Viability Scan provides much more information about the fetus than just the date of the pregnancy.
At 8 weeks, the fetus is just as big as a grape and has started to develop the majority of its organs. The main purpose of this scan is to confirm the heartbeat as well as:
- Check for single/multiple pregnancies*,
- Date the pregnancy: estimation of gestational age (pregnancy age in weeks) and the EDD (estimated date of delivery),
- Check main structures of the gestational sac, which include the baby (the embryo), the yolk sac, and the future placenta,
- Examine for any early pregnancy abnormalities.
*For multiple pregnancies (i.e. twins, triplets, etc.) it is extremely important to know the type of placentation (do the babies share the same placenta or do they have separate placentas?). This is important for the prediction of certain complications.
What makes our Viability Scan different?
We use an advanced ultrasound scanner with unique high-resolution probes.
The benefits of this include:
- We do not need you to have a full bladder for the scan,
- In most cases, the technology we use allows the Viability Scan to be performed transabdominally (the transducer is placed over your belly),
- We do not only date the pregnancy, but also examine how it is developing,
- We can offer NIPT (non-invasive prenatal testing: Harmony Test) during the same appointment if we find that you are past your 10th week of pregnancy (please note that we do NIPT only in conjunction with the Early Baby Scan, which we perform from 12 weeks)
Should I have the Viability Scan?
The Nuchal Translucency (NT) scan is the first scan offered by NHS hospitals, which is performed at 11-13 weeks. It is used to date the pregnancy; however, it provides a less accurate EDD (estimated date of delivery).
The Viability Scan will:
- Let you know how many babies you will have,
- Be able to tell the precise date of the pregnancy and estimated delivery,
- Allow you to take a NIPT as early as possible (if we recognise that the baby is at least 10 weeks),
Allow you to create a detailed schedule of your follow-up scans, which means you can schedule in your other activities (such as business trips or holidays) around this.
What is the optimal time to perform Viability Scan?
The optimal gestational age for the scan is from 8-11 weeks.
However, if you wish to have NIPT during the same appointment, then we must ensure that you are at least 10 weeks along.
Can the viability scan be used to diagnose any anomalies?
Depends on how far along you are when we perform the scan (weeks of pregnancy).
Unfortunately, before 11 weeks the baby has not finished its primary development and is still considered an embryo. Therefore, it is not possible to exclude any anomalies.
However, from 11 weeks the baby is considered a fetus, meaning it is fully formed and resembles a tiny human. This means that our ultrasound scanners, which are specially designed to obtain high-resolution images, can be used to examine the fully developed structures of the fetus, such as the heart. The Early Baby scan can be performed as early as 11 weeks of pregnancy; however we will have to use a specifically-designed high resolution transvaginal probe to obtain these images. Please note that the Early Baby Scan is a much more comprehensive examination of the fetus and has different pricing to the Viability Scan.
Should I get the NIPT at 10 weeks after my Viability Scan?
It may be best to delay the NIPT until your scan at 12 weeks. However, we are aware that the majority of NIPT providers in London and around the globe advise performing the test at 10 weeks together with a viability scan. The benefit of this approach is that the test is performed as early as possible.
We believe is it better to perform NIPT at 12 weeks and performing the test at 10 weeks has serious limitations because:
- At 10 weeks the baby is still an embryo and has not completed its development, making it impossible to examine its anatomy in order to exclude any physical (structural) abnormalities, which can be serious or even lethal. Statistically, structural anomalies are more common than Down’s Syndrome (a chromosomal anomaly), therefore it is important to investigate the physical anatomy of the baby.
- It is impossible to assess nuchal translucency (NT) thickness, which is used as an independent non-specific marker for fetal wellbeing. A baby with an increased NT has a greater chance of chromosomal anomalies even if NIPT results are negative and an invasive test is offered.
In order to avoid false reassurance from a negative NIPT result, we believe that waiting to perform the test at 12 weeks increases the window of opportunity for detecting fetal anomalies. There have been cases where individuals have received the NIPT test with a negative result and thus been reassured regarding the health of their baby, only to discover significant health problems that could have been diagnosed just a few days or weeks later.
Keeping this in mind, we have developed a screening package called the Early Baby Test (performed at 12 weeks), which includes the Early Fetal Scan and NIPT.