Early pregnancy screening for fetal aneuploidy with serum markers and nuchal translucency.
We determined the aneuploidy detection rate achievable by early pregnancy screening with pregnancy associated plasma protein (PAPP)-A, free beta human chorionic gonadotrophin (hCG) and ultrasound nuchal translucency (NT) measurement. Women having prenatal diagnosis were scanned, and a blood sample was taken and stored. Stored samples were tested and a total of 37 were found to have Down syndrome, 8 to have Edwards syndrome and 255 were controls. Results were expressed in multiples of the gestation-specific median (MOM) value in the controls after regression and, for the serum markers, maternal weight adjustment. In Down syndrome the medians were for PAPP-A 0.63 MOM (95 per cent confidence interval (CI) 0.45-0.87); free beta-hCG 1.88 MOM (1.33-2.66); and NT 2.34 MOM (1.70-3.22). Using these parameters the expected detection rate for a 5 per cent false-positive rate for different marker combinations were: 55.3 per cent for PAPP-A and free beta-hCG; 68.4 per cent for NT alone; and 84.6 per cent for PAPP-A, free beta-hCG and NT. The median values for Edwards syndrome were: 0.17 MOM for PAPP-A; 0.18 MOM for free beta-hCG; and 2.64 MOM for NT. Early pregnancy screening with the combined measurement of maternal serum PAPP-A and free beta-hCG and fetal nuchal translucency could achieve a high Down syndrome detection rate.
de Graaf
I M
IM
Department of Obstetrics and Gynaecology, Academic Medical Centre, Amsterdam, The Netherlands. I.M.deGraaf@AMC.UvA.NL
Pajkrt
E
E
Bilardo
C M
CM
Leschot
N J
NJ
Cuckle
H S
HS
van Lith
J M
JM
D000782:Aneuploidy; D015415:Biomarkers / Q000032:analysis*; D016022:Case-Control Studies; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D004314:Down Syndrome / Q000097:blood* / Q000000981:diagnostic imaging* / Q000235:genetics; D005260:Female; D005315:Fetal Diseases / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D006801:Humans; D016011:Normal Distribution; D011237:Predictive Value of Tests; D011247:Pregnancy; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis; D011296:Prenatal Diagnosis / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D014463:Ultrasonography; D000509:alpha-Fetoproteins / Q000032:analysis
D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D000509:alpha-Fetoproteins; D011266:Pregnancy-Associated Plasma Protein-A