Noninvasive DNA testing is usually more accurate in determining trisomy 21, trisomy 18, and trisomy 13, and less accurate in testing for other chromosomes, so other chromosomes are usually not checked. Non-invasive DNA is a more common test for women during pregnancy and is an important way to screen the fetus for chromosomal abnormalities. The test focuses on chromosomes 18, 13 and 21 and is relatively accurate. However, for other chromosomes, the accuracy of non-invasive testing is not very high, so the need for testing is not very high. In order to timely detect diseases or fetal abnormalities during pregnancy, it is recommended to have regular medical checkups and early formal treatment after detection.