What are prenatal diagnostics?

Further testing

If the result of the combination test or the NIPT shows an increased risk of a chromosome defect, then you can choose for further testing:

  • A chorin villus sampling – the harvesting and analysis of a piece of tissue from the placenta;
  • Or an amniocentesis – the harvesting and analysis of amniotic fluid.

The chance of a miscarriage following an amniocentesis or a chorion villus sampling is 2 in the 1000 tests. This chance is slightly higher with a chorion villus sampling compared to an amniocentesis. It is your decision whether you want to accept this risk or not. 

If you have chosen for a combination test and the result shows an increased risk, then you can also choose to do a NIPT test.  The NIPT falls under prenatal screening.

If the 20-week scan shows a structural anomaly then further testing is an advanced ultrasound scan (GUO). This test does not carry a risk of miscarriage. Depending on the findings, you may be offered an amniocentesis for more information. 

Further testing is covered by your health insurance.


The Erfocentrum is an independent non-profit organisation that offers the public information about hereditary issues and health. The Erfocentrum has a general information website: www.erfelijkheid.nl and a website specifically for (future) pregnancy: www.strakszwangerworden.nl. You can also find information on the RIVM and De Verloskundige websites.

Not mandatory!

You are not obliged to choose to have further testing done. You can decide at any time to not carry out any further testing. Whatever your decision, this will not effect your medical care.