The result of Down’s syndrome screening test for trisomy 21 shows high risk, indicating that the fetus has congenital genetic problems. In this case, the fetus is more likely to develop pediatric Down’s syndrome after birth, and further tests are needed to confirm the diagnosis. It is recommended that pregnant women choose non-invasive DNA testing, which is performed by drawing the mother’s peripheral blood and testing the fetus’ chromosomes to determine the presence of the disease. This method is not damaging to the fetus and is generally easy to accept. It is suitable for those who are more than 12 weeks pregnant, but the accuracy rate is not 100%. If the results of the non-invasive DNA test show that the risk is still high, further amniocentesis is required to confirm the diagnosis. Amniocentesis is indicated for pregnant women at 16-20 weeks of pregnancy and can clarify the presence of trisomy 21 in the fetus. However, amniocentesis can be dangerous for the fetus and the pregnant woman. Inadequate preparation and improper operation can lead to maternal infection and fetal miscarriage. If the test confirms the diagnosis of trisomy 21, the pregnancy needs to be terminated promptly. Therefore, Down’s syndrome screening for trisomy 21 can only play a reference role, and follow-up tests should be actively improved to determine fetal growth and development. During pregnancy, attention should be paid to stay away from radiation and other undesirable environments, not to go to places with air pollution, ensure sufficient sleep and reasonable exercise, and avoid violent mood swings, which can reduce the risk of fetal developmental malformations.