I am 18 weeks pregnant and have a high risk of Down syndrome based on the screening test.

Patient's question:

I am 18 weeks pregnant with a high risk of Down syndrome screening for trisomy 21. Risk value: 1 in 100

Doctor's answer:

Analysis of the condition: Hello, Down syndrome is also known as trisomy 21, which means the patient has one extra chromosome in the 21st pair (while the normal number is one pair). Down syndrome screening is performed by calculating the risk value based on the levels of AFP and HCG in the pregnant woman's serum, combined with her age, weight, and gestational age. The critical value is 1/275. A value greater than this indicates a high risk, while a value lower than this indicates a low risk.
Recommendation: If the results of the Down syndrome screening suggest a high risk of the fetus having Down syndrome, further confirmatory tests such as amniocentesis or chorionic villus sampling should be conducted.