There is no need to be too nervous and worried because the accuracy of Down’s syndrome screening is only 65% and not 100%. If the symptoms appear, further non-invasive DNA testing is required. During the 13-20 weeks of pregnancy, non-invasive DNA testing is performed by taking the serum of the pregnant woman to determine whether the fetus has congenital dysmorphism. In general, the accuracy of non-invasive DNA can reach more than 90%. If there is still a risk in doing non-invasive DNA, further amniocentesis is required, which is the final result and the gold standard to determine whether the fetus has any problems.