From Biomarkers to Risk Scores: Maternal First Trimester Dual Marker Screening, Risk Stratification for Trisomy 21/18/13

Background Prenatal screening plays a vital role in identifying pregnancies at increased risk for chromosomal conditions such as Down’s syndrome (Trisomy 21), Edwards syndrome (Trisomy 18), and Patau syndrome (Trisomy 13). First trimester screening combines maternal serum biomarkers—free β-Human Chorionic Gonadotropin (β-HCG) and Pregnancy Associated Plasma Protein A (PAPP-A)—with ultrasound parameters like Nuchal Translucency (NT) and Crown Rump Length (CRL). These inputs, when analyzed using validated software such as SSDW, allow for early, non-invasive risk stratification. By integrating biochemical and sonographic data, this approach supports timely clinical decisions and minimizes the need for invasive diagnostic procedures.