Is early prenatal screening the same as NT screening?

Patient's question:

No

Doctor's answer:

Hello, NT screening and Down syndrome screening are both used to assess fetal health, so both methods can screen for fetal health in the early stages. In summary, NT is a 21-trisomy screening using ultrasound around weeks 11-13, while Down syndrome screening involves serum blood markers for screening around weeks 15-18. These are different-stage, different-method examinations, and sometimes both tests need to be combined.