Serum PAPP-A and free beta-hCG are first-trimester screening markers for Down syndrome.
Serum measurements of pregnancy-associated plasma protein A (PAPP-A) and the free beta-human chorionic gonadotrophin (hCG) subunit were made in 13 women with Down syndrome (DS) pregnancies and six other women with fetal aneuploidy ascertained at chorionic villus sampling (CVS), as well as 89 women with contemporaneous normal control pregnancies. Median serum PAPP-A measurements (0.31 MOM, 95 per cent confidence interval (CI) 0.22-0.65 vs. normal 1.06, 95 per cent CI 0.89-1.20) were lower and free beta-hCG subunit measurements (1.13 MOM, 95 per cent CI 0.93-2.63 vs. normal 0.91, 95 per cent CI 0.79-1.03) were higher at statistically significant levels. Receiver operator characteristics (ROC) curves showed that the highest sensitivity for detection, 71.2 per cent (95 per cent CI 54.7-87.6 per cent), was for depressed PAPP-A levels; the combination of low serum PAPP-A levels, maternal age, and elevated free beta-hCG levels yielded a detection rate of 78.9 per cent (95 per cent CI 64.9-92.8 per cent) of the affected pregnancies at 8-12 weeks' gestation.
Brambati
B
B
Istituto Ostetrico e Ginecologico L. Mangiagalli, University of Milan, Italy.
Tului
L
L
Bonacchi
I
I
Shrimanker
K
K
Suzuki
Y
Y
Grudzinskas
J G
JG
D000328:Adult; D000782:Aneuploidy; D015415:Biomarkers / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood*; D018997:Chorionic Gonadotropin, beta Subunit, Human; D015193:Chorionic Villi Sampling; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D010446:Peptide Fragments / Q000097:blood*; D011247:Pregnancy; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis*; D012372:ROC Curve; D011863:Radioimmunoassay; D012189:Retrospective Studies
D015415:Biomarkers; D006063:Chorionic Gonadotropin; D018997:Chorionic Gonadotropin, beta Subunit, Human; D010446:Peptide Fragments; D011266:Pregnancy-Associated Plasma Protein-A