This test involves a blood test that measures the quantity of two chemicals in the mother’s blood – free beta-hCG(Human Chorionic gonadotrophin) and PAPP-A(Pregnancy Associated Plasma Protein-A).The first trimester screening blood test can be done at anytime from 10-13+6 weeks of pregnancy.
Double Marker Test
Quadruple Test
The composition of certain “Feto-Placental” chemicals can be tested in the maternal serum between 15-22 weeks to establish the risk for fetal aneuploidies. The relative proportion of these chemicals change in pregnancies associated with chromosomal abnormalities and this is the rationale of evaluating the quantity of these substances.
NIPT
NIPT (cell free fetal DNA testing) is a non invasive prenatal testing with higher sensitivity for predicting chromosomal aneuploidies. NIPT is based on the analysis of cell free fetal DNA present in the sample of maternal blood to determine the likelihood of chromosomal aneuploidies.
Good pre test and post test counseling is essential for better use of NIPT. It is useful to reassure the couple as it is a good screening test with good negative predictive value.
