California Prenatal Screening Program CPSP FIRST TRIMESTER COMBINED = NT Plus 1 st Trimester Analytes FULL INTEGRATED = NT Plus 1st & 2 nd Trimester Analytes SERUM INTERGRATED = 1st & 2 nd Trimester Analytes Only QUAD SCREEN ONLY = 2 nd Trimester Analytes Only
NUCHAL TRANSLUCENCY (NT) What Is It? NT is the sonolucent zone at the posterior aspect of the fetal neck. This space represents the sonographic appearance of subcutaneous fluid behind the fetal neck.
Earlier results with analytes drawn as early as 10 weeks 0 days & NT performed @ 11 1/2 weeks. The CPSP allows an Instant Risk Calculation with the addition of the NT measurement when analytes are available.
If a woman is found to be at an increased risk for fetal aneuploidy, she can be offered genetic counseling and choose to proceed with CVS as early as 11 ½ weeks providing chromosome results @ 12 ½ weeks EGA
For women < 35 yo t he first trimester combined result is PRELIMINARY and will detect ~ 62% of babies affected with a Down syndrome utilizing the CPSP screen positive cut off of 1 %.
To complete the full integrated CPSP program a second blood test ( Quad Screen) is required between 15 and 20 weeks which allows the test to detect an additional 20 % or more of Down syndrome babies for a final detection rate of ~ 85 %.
Overall < 5 % of patients may have a positive test in the second trimester indicating an increased risk for a genetic birth defect.
NT MORE THAN 99 PERCENTILE 3.5 OR MORE FROM 45-84 MM
PAPP -A Low levels in the first trimester have been associated with preeclampsia, fetal growth restriction, preterm birth, and fetal demise. PAPP-A levels less than the 5%tile are associated with a 1 to 4 %risk of pregnancy loss before 20 weeks, and increased risk of IUGR wit a PPV of up to 24%.
hHCG Low levels (below the 5%tile) in the first trimester have been associated with a 1-4% risk of pregnancy loss before 20 weeks. hHcg levels below the 1%tile have been associated with significantly increase drisk of IUGR with a PPV of 14%.