Patient's question:
Hello. Doctor. I would like to ask. I had a BC scan at 12 weeks, and all other data was good, except the NT value was 3.00 mm. Then, during the first prenatal screening blood test, the values for trisomy 21 and trisomy 18 were: 21 (1:7600) and 18 (1:100000), respectively. Could you please tell me if these values are high risk or low risk? I look forward to your reply. Thank you.Doctor's answer:
Analysis of the condition: 1. Down syndrome, also known as trisomy 21, refers to a condition where the patient has an 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 the pregnant woman's age, weight, and gestational age. The critical value is 1/275. A value greater than this indicates high risk, while a value lower than this indicates low risk. The probability of having Down syndrome (DS) in the general population (under 37 years old) is 1/750.Recommendations: If the screening result is high risk, it is recommended to undergo amniocentesis. However, even if the result is high risk, it does not necessarily mean the child has Down syndrome. For safety's sake, it is still advisable to undergo DS screening! Children with Down syndrome have severe intellectual disabilities, cannot live independently, and often suffer from complex cardiovascular diseases, requiring long-term care from family members. This can impose a significant emotional and financial burden on the family.