At Femme Amsterdam we offer prenatal screening tests. Thanks to these tests, it can be investigated whether your child has a chromosomal, genetic and / or physical abnormality. The NIPT specifically look at Down, Pateau and Edwards syndrome. With all these syndromes, three chromosomes are present instead of two chromosomes. Additional findings such as other genetic abnormalities in the child, abnormalities in the placenta or abnormalities in the mother can also be found if you wish that this is also looked at. The 3 and 20-week ultrasound looks at structural (physical) abnormalities of the unborn child.
Prenatal screening is not mandatory, if you want information about this, we will provide you with information during a counseling interview during your first meeting and consider the pros and cons of testing with you.
Several prenatal screening tests
There are various prenatal screening tests, such as the NIPT, the IMITAS study, also called 13 week ultrasound and the Structural Ultrasound Examination, also called SEO or 20 week ultrasound. All of these tests are non-invasive. This means that the tests pose no risk to your baby. If the prenatal screening shows that there is an increased risk of a chromosomal, genetic or physical condition in your child, you are eligible for an interview at the prenatal diagnosis department in the hospital. Then you can choose to do nothing or have a chorionic villus sampling or amniocentesis performed, where a result can mostly tell you whether your baby is having the condition you are looking for or not.
To prepare for the first interview with your midwives, you can prepare by reading more information about prenatal testing. Read here for more information and here (clinical studies also in English).
Trident 2 studie NIPT
The Dutch NIPT test (Non-invasive Prenatal Test) can be conducted as early as 10 weeks’ gestation. Your blood sample will be analysed for potential chromosomal or genetic disorders affecting your unborn child. This can be determined as your blood shares DNA found in the placenta. This is often the same as that of your baby which means certain indicators for Down, Edwards or Patau syndrome can be identified. If you desire you can also screen for more rare conditions. If an increased risk of a disorder is detected, you can elect to have further testing conducted by meaning of prenatal diagnostics; this provides 100% certainty. You can find here more information in English.
13 week ultrasound
The 13-week ultrasound (the official name is the First Trimester Structural Ultrasound Examination) is an ultrasound that will be offered to all pregnant women in a study context from September 1, 2021. It is performed between 12+3 and 14+3 weeks. The bigger the child, the better body structures can be assessed. The 13-week ultrasound is a medical examination for physical abnormalities in your baby. The 13 week ultrasound is very similar to the 20 week ultrasound. In both examinations, a sonographer uses an ultrasound machine to check whether your child has any physical abnormalities. The sonographer will tell you the results immediately after the ultrasound. In 95 out of 100 pregnancies, the sonographer sees no indication of an abnormality. No further investigation is then necessary. In about 5 out of 100 pregnant women, the sonographer sees something that could be an abnormality. It is not always immediately clear whether it is indeed an abnormality, how serious the abnormality is and what this means for your child. Did the sonographer see anything abnormal? You can then opt for further research.
This will first consist of an extensive ultrasound examination. This is called: an advanced ultrasound examination (GUO). This examination is similar to the 13-week ultrasound but often takes longer. The specialist sonographer in the hospital, the Center for Prenatal Diagnostics, can see more details of the child. Sometimes another specialist supervises the examination. The examination does not hurt and is not harmful to your child. Sometimes the doctor afterwards suggests a blood test, chorionic villus sampling or amniotic fluid test. This depends on the abnormalities found during the ultrasound examination. The doctor will explain it all to you first. You decide if you want to choose for this tests or not. You can find here more information in English.
Structural ultrasound examination (SEO) is used to look for structural (physical) abnormalities of the unborn child. The SEO can be performed between week 18+0 and week 21+0 of the pregnancy, and preferably between weeks 19+0 and 20+0 of the pregnancy. Even in the case of an incomplete SEO due to insufficient imaging, the repetition of the SEO must be completed before 21+0. The reason for this is that follow-up investigations are often time-consuming when abnormalities are found. After the outcome of the follow-up examination, there must be sufficient time for you as a pregnant woman and your partner to consider whether or not you want to continue the pregnancy.
If one of the prenatal tests shows that there is an increased risk of a chromosomal, genetic or physical abnormality, you can choose to let prenatal diagnostic tests performed. These tests determine with a high degree of certainty whether or not your child has an abnormality. Forms of prenatal diagnosis are:
- Chorionic villus sampling – a piece of tissue from the placenta is removed and examined. This examination can be done from 11 weeks. The results are usually there after 2 weeks. A chorionic villus sampling test provides certainty in 98 to 99 out of 100 cases (98-99%) whether or not your child has the condition that has been researched.
- Amniocentesis – a small amount of escape water is taken and examined. This examination can be done from 16 weeks. The result will then be available within 3-5 days. The examination can determine with almost absolute certainty whether or not your child has an abnormality.
These tests are invasive, meaning there is a small chance of miscarriage. The chance that this happened during the amniocentesis and chorionic villus sampling is approximately 2:1000 or 0.2%.
frequently asked questions
Veelgestelde vragen over prenatale testen
NIPT: When the results indicate an increased risk of:
- Trisomy 21, there is a 96% chance of the baby having trisomy 21 and a 4% chance that the baby does not have trisomy 21.
- Trisomy 18, there is a 98% chance of the baby having trisomy 21 and a 2% chance that the baby does not have trisomy 18.
- Trisomy 13, there is a 53% chance of the baby having trisomy 21 and a 47% chance that the baby does not have trisomy 13.
13 weeks ultrasound: The sonographer sees something that could be an abnormality in about 5 out of 100 pregnant women. It is not always immediately clear whether it is indeed an abnormality, how serious the abnormality is and what this means for your child.
NIPT: When the results indicate that there is not an increased risk of:
- Trisomy 21, 18 and 13: There is a 99 % chance that the baby does not have trisomy 21, 18 and 13 and a 1% chance of the baby having trisomy 21, 18 and 13, also known as < 1:1000
NIPT: Yes, Findings other than trisomy 21, 18, or 13 can be reported on request. These included other trisomies (0.18%, PPV 6%), many of the remaining 94% of cases are likely confined placental mosaics and possibly clinically significant, structural chromosomal aberrations (0,16%, PVV 32%) and complex abnormal profiles indicative of maternal malignancies (0.02%, PPV 64%).
Structural 20 week ultrasound: This examination checks for structural (physical) abnormalities of the unborn child. It may be that a child with a chromosome abnormality looks normal on the 20-week ultrasound, so it can occur that a chromosomal abnormality is not always detected at this 20 weeks ultrasound.
13 weeks ultrasound: At 13 weeks, a screening is performed for structural (physical) abnormalities of the unborn child. It is possible that a child with a chromosome abnormality looks normal on the 13-week ultrasound, so that the chromosome abnormality is not always detected at that time.
Trident-2 study NIPT: €175. Test for chromosome 13, 18, 21 and if desired for incidental findings.
Structural ultrasound examination (SEO): Is reimbursed by the health insurer, if you are not insured, the SEO costs € 179.28
13-week ultrasound: will be reimbursed from the national budget, given that this is still a subsidized study (IMITAS study).
NIPT: No, the test identifies:
- 97 out of 100 children with trisomy 21
- 90 out of 100 children with trisomy 18
- 90 out of 100 children with trisomy 13
NIPT’s Trident-2 study is still ongoing. These results are based on 73.239 studies.
Structural 20 week ultrasound: this ultrasound is not a genetic investigation and, for example, intellectual disabilities cannot be established. Also not all physical abnormalities can be seen with an ultrasound around the 20-week pregnancy. It is important to realize these limitations of SEO.
13 weeks ultrasound: the 13-week ultrasound is not a genetic test and, for example, intellectual disabilities cannot be determined. Also not all physical abnormalities can be seen with an ultrasound around 13 weeks of pregnancy. It is important that you realize these limitations of the 13 week ultrasound.
NIPT: Within 12 days
Structural 20 week ultrasound: The sonographer will tell you what see sees during the ultrasound, if she thinks there might be an abnormality she has to tell you immediately.
NIPT: From 11 weeks’ gestation
Structural 20 week ultrasound: Preferably between 19+0 and 20+0 weeks. It can be done exceptionally from 18+0 weeks. Preferably not later than 20 weeks, but can be done up to 21+0 weeks. Bear in mind that if a abnormality is seen, you will then have a very short period of reflection to make any decisions about the pregnancy.
13 weeks ultrasound: The 13 week ultrasound can be done between 12+3 and 14+3 weeks. It is preferable to do the 13 week ultrasound between 13+0 and 14+3 weeks because you can assess more body structures when the baby is bigger.
NIPT: For the NIPT, the so-called counting method is used. The number of chromosomes in the DNA found within the placenta is counted. This method can now also be used for twins.
Structural 20 week ultrasound:An ultrasound technician provides an ultrasound image during the 20 weeks of ultrasound over the entire anatomy, from top of the head to the toes of your baby. The bigger the baby gets, the better body structures are visible with ultrasound.
13 weeks ultrasound: An ultrasound technician provides an image of the entire anatomy by means of an ultrasound examination, from top of the head to the toes of your child.
NIPT: Yes, this test is used in scientific research. You will provide permission for the use of your data. If you do not provide permission, you will not be able to undertake the Dutch NIPT because this test includes automatic participation in a research study. To be able to choose for the Dutch NIPT you need to have a personal security number (BSN).
- An early ultrasound seems to be to the advantage of pregnant women. You can then know early on in the pregnancy whether the child has a serious physical abnormality. This gives you more time for additional research and to decide what to do with the results.
- On the other hand, an early ultrasound may also cause additional unrest and uncertainty.
In the NIPT test, blood is taken from the mother in which the placental DNA is examined.
The 13 and 20 week ultrasound is done by a sonographer with an ultrasound machine that emits harmless sound waves which are then converted into images and show the baby’s anatomy on a screen.