For pregnant women whose early screening for Down’s syndrome indicates a high risk, it is advisable to have an amniocentesis. Non-invasive DNA is a more advanced and accurate screening test than early Down’s screening, but it is not the final confirmatory test. If the Down’s syndrome screening is a critical risk, it is usually okay to do non-invasive DNA. However, for high-risk pregnancies, doing an amniocentesis is more accurate. This is because non-invasive DNA is usually done for only three pairs of chromosomes and is not always able to detect other chromosomal disorders. Amniocentesis, on the other hand, examines all chromosomes, so it is more accurate and reliable. For pregnant women with high risk of Down’s syndrome screening and those older than 35 years old, it is recommended to have an amniocentesis.