The day before the Down’s syndrome screening, you should pay attention to a light diet, adequate rest, etc.. 1. Light diet: Down’s syndrome screening is a serological examination conducted between 15 and 20 weeks of pregnancy, screening for aneuploidy chromosomal abnormalities mainly due to Down’s syndrome, which requires the extraction of peripheral blood of pregnant women for examination, and attention should be paid to a light diet the day before the screening, so as not to affect the results of the examination. 2. Sufficient rest: also sufficient rest to ensure adequate sleep, pay attention not to stay up late, and do not strenuous exercise and exertion, may also affect the results of the test. Down’s syndrome screening is a prenatal screening method for low-risk pregnancies. Negative results do not mean that everything is normal, and you should follow the doctor’s instructions to continue with the follow-up examination.