When should I have a non-invasive DNA test? Non-invasive DNA, also known as NIPT, is one of the prenatal diagnostic tools. Generally speaking, NIPT can be considered for pregnant mothers who are of advanced age, have widened NT, are at high risk for Down’s syndrome or have other medical indications and do not want to undergo invasive prenatal testing for prenatal diagnosis. Does non-invasive DNA testing affect the pregnancy and the fetus? Non-invasive DNA is a test that takes the mother’s blood and has no effect on the fetus or the mother. How accurate is the non-invasive DNA test? The principle of non-invasive DNA is to quantify the free DNA in the mother’s serum. The accuracy is still very high, reaching 99% or more, and can basically exclude chromosome 13, 18 and 21 trisomy. However, for patients who have twin pregnancies in early pregnancy and then one of the pregnancies is aborted, or who have had a chromosomal abnormality induced in the previous pregnancy for less than 2 years, we recommend that screening by Down’s syndrome or amniocentesis is preferable.