The prenatal screening report includes the maternal age and age at expected delivery, specimen number, gestational week at screening and method of derivation, test value and MOM value (median multiple, which is the expected/normal intermediate concentration of a given test concentration divided by the expected/normal intermediate concentration of an analyte) for each screening indicator, corrected risk level for the screening target disease, and relevant tips and recommendations. Normal test results: risk of trisomy 21 ≤ 1/270; risk of trisomy 18 ≤ 1/350; risk of neural tube defects: screening negative. High risk indicators: trisomy 21 risk ≥ 1/270; trisomy 18 risk ≥ 1/350; positive risk of neural tube defects; β-hCG ≤ 0.25 MoM; AFP ≤ 0.40 MoM. Meaning of indicators: AFP: also known as serum alpha-fetoprotein, is a fetal specific globulin, which can have immunomodulatory function of glycoprotein during maternal pregnancy and can prevent fetal rejection by the mother. rejection by the mother. β-hCG: HCG is a human chorionic gonadotropin synthesized by placental cells and consists of two subunits, α and β. HCG enters the maternal blood after fertilization and proliferates rapidly until the 8th week of pregnancy, then decreases slowly until the 18th-20th week of pregnancy, when it remains stable. Related indicators Human chorionic gonadotropin free beta subunit, pregnancy-associated plasma protein-A, fetal nuchal translucency thickness, methemoglobin, human chorionic gonadotropin, unconjugated estriol, inhibin A.