Hello doctor, Which test should be done prior? NTNG scan or dual marker for pregnant women? LMP was two months back.
Hello. First-trimester screening for Down's syndrome should be done in all pregnancy between 11 to 14 weeks. The first-trimester screening for Down's syndrome includes USG for NT/NB scan and on the same day, blood is taken for the dual marker (BhCG and PAPA-A). Thereafter, using maternal age, values of NT scan and values of BhCG and PAPP-A, a risk ratio if Down's syndrome is obtained using computer software.