Noninvasive DNA during pregnancy shows low risk and is not 100% safe, as the test is not 100% accurate. Non-invasive DNA testing is a method of screening for common aneuploidy chromosomal abnormalities based on the free DNA information of fetal origin in the plasma of pregnant women. Currently, second-generation sequencing and information biology technologies are generally used, and the accuracy of screening is relatively high, with the detection rates of 99%, 97%, and 91% for trisomy 21, trisomy 18, and trisomy 13 screening, respectively. Although the accuracy of this test is relatively high, if the fetus has other chromosomal abnormalities or genetic disorders, or even fetal structural malformations, the non-invasive DNA test may not be able to detect them, and the diagnosis is usually made through amniocentesis or umbilical vascular puncture. Therefore, although non-invasive DNA test is low-risk, it does not guarantee that the fetus will be free of problems, and it is necessary to have regular obstetric checkups to detect problems in time.