Amniocentesis is not performed before 16 weeks. The procedure lasts 1-2 minutes and is performed under scan guidance. A fine needle is passed through the abdomen and amniotic Fluid around the baby is taken and tested for abnormalities.

Many women find the procedure uncomfortable rather than painful, and describe feeling period-type pains. However, it’s over relatively quickly. The test lasts no longer than half an hour from start to finish and actually taking the sample is only a matter of a few minutes

The results for Down’s syndrome and other major chromosomal defects are usually available within 3 days. The results for rare defects take 2 weeks.


The risk of miscarriage due to amniocentesis is about 1% and this is the same as the risk from chorion villus sampling.In approximately 1:1000 cases the test will need to be repeated because the results are inconclusive. If you were to miscarry due to the test, this would happen within the next five days

Some studies have shown that when amniocentesis is performed before 16 weeks there is a small risk of the baby developing club feet. To avoid this risk we never perform amniocentesis before 16 weeks.

If we suspect there is a problem with your baby, we can refer you to an expert who specialises in Amniocentesis.