If you have a high risk of trisomy 21, don’t worry too much if you have a Down’s syndrome screening test, because the accuracy rate of Down’s syndrome screening can only reach 65%, you can do further tests, non-invasive DNA test, by taking the pregnant woman’s blood serum, then comprehensive analysis of the specific development of the fetus, combined with the pregnant woman’s weight and pregnancy week comprehensive assessment, the accuracy rate of non-invasive DNA can The accuracy of non-invasive DNA can reach 99%. If there are still problems with non-invasive DNA, further amniocentesis is needed. Amniocentesis directly extracts amniotic fluid to directly analyze the development of the fetus, which is the final result and is more accurate and scientifically based.