Non-invasive is also known as non-invasive DNA, 40 years old pregnant women can do non-invasive DNA test, non-invasive DNA has abnormalities and then do amniocentesis test. Non-invasive DNA is to extract the serum of pregnant women, according to the age of pregnant women, pregnancy weeks, height, weight, etc., to comprehensively analyze, judge, assess the specific symptoms of the fetus, to determine whether the fetus has congenital genetic aspects of the problem, this test is non-invasive, the impact on the pregnant woman and the fetus is relatively small, the 40-year-old pregnant women of advanced age can be the first to do non-invasive DNA. Do non-invasive DNA test for high risk, this does not pass the case and then do amniocentesis test, amniocentesis is an invasive test, on the pregnant woman and the fetus may cause some harm, improper operation will lead to infection of the uterine cavity, amniotic fluid outflow, increase the chances of preterm preterm labor and miscarriage of the fetus. Pregnant women of advanced age should do a good job of maternity checkups during pregnancy and deal with any abnormalities in a timely manner.