Combined First-Trimester PAPP-A and Free β-hCG Levels for the Early Diagnosis of Placenta Accreta Spectrum and...

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Biochemical Markers in Pregnancy

Background:

• Placenta accreta spectrum (PAS) and placenta previa (PP) are severe obstetric disorders with significant maternal and perinatal morbidity.
• Early diagnosis of PAS and PP is challenging, especially with subtle imaging findings.
• First-trimester screening is crucial for identifying high-risk pregnancies.

Purpose of the Study:

• To evaluate the diagnostic value of first-trimester maternal serum levels of pregnancy-associated plasma protein-A (PAPP-A) and free beta subunit of human chorionic gonadotropin (β-hCG) in predicting PAS and PP.
• To assess the combined diagnostic accuracy of these biomarkers.

Main Methods:

• Retrospective case-control study including 100 pregnant women (36 PAS, 32 PP, 32 controls).
• Maternal serum levels of PAPP-A and β-hCG measured at 11-13⁶ weeks of gestation.
• Receiver Operating Characteristic (ROC) analysis used to evaluate diagnostic performance.

Main Results:

• PAPP-A levels were significantly lower, and β-hCG levels were significantly higher in both PAS and PP groups compared to controls (p < 0.001 for most comparisons).
• Combined biomarker modeling demonstrated improved diagnostic accuracy.
• Area Under the Curve (AUC) reached 0.85 for PAS (85.2% sensitivity, 72% specificity) and 0.88 for PP (100% sensitivity, 72% specificity).

Conclusions:

• First-trimester maternal serum PAPP-A and β-hCG levels are significantly altered in pregnancies with PAS and PP.
• The combined dual-marker approach enhances the early detection of PAS and PP.
• Integrating biochemical screening into first-trimester risk assessment protocols can improve early identification, timely referral, and reduce adverse outcomes.