The "Consecutive Combined Test": using double test from week 8 + 0 and nuchal translucency scan, for first trimester screening for Down syndrome

TY - JOUR

T1 - The "Consecutive Combined Test"

T2 - using double test from week 8 + 0 and nuchal translucency scan, for first trimester screening for Down syndrome

AU - Schiøtt, Kirsten Marie

AU - Christiansen, Michael

AU - Petersen, Olav Bjørn

AU - Sørensen, Tina Lind

AU - Uldbjerg, Niels

N1 - 2006 John Wiley & Sons, Ltd.

PY - 2006

Y1 - 2006

N2 - OBJECTIVE: To test the performance of the "Consecutive Combined Test", applied on a high-risk population. The classic "Combined Test" (Double test (DT) and Nuchal Translucency (NT) measurement on the same day at app. week 12) gives detection rates (DR) for Down syndrome (DS) of 80-90% for false positive rates (FPR) of 5%. In affected pregnancies, however, the low PAPP-A level is more pronounced, the earlier in pregnancy. Thus, we hypothesized that the Double Test could be taken as early as from week 8 + 0, without compromising the excellent performance of the Combined Test. This "Consecutive Combined Test" allows for a centralised laboratory function.METHODS: Inclusion criteria were maternal age > 35 years (80%) or a family history (20%). Double test was taken at a median gestational age (GA) = 10 weeks. NT was measured at GA = 11 + 0 - 13 + 6. A combined risk estimate of > 1:400 at birth was used as cut-off.RESULTS: 881 had the full test. Screen positive = 34. CVS with aneuploidy = 11 (6 trisomy-21, 5 others). FPR = 3.2%. Positive Predictive Value (PPV) = 17.6% for T-21.CONCLUSION: The "Consecutive Combined Test" applied on a high-risk population seems to be highly efficient with a remarkably high PPV.

AB - OBJECTIVE: To test the performance of the "Consecutive Combined Test", applied on a high-risk population. The classic "Combined Test" (Double test (DT) and Nuchal Translucency (NT) measurement on the same day at app. week 12) gives detection rates (DR) for Down syndrome (DS) of 80-90% for false positive rates (FPR) of 5%. In affected pregnancies, however, the low PAPP-A level is more pronounced, the earlier in pregnancy. Thus, we hypothesized that the Double Test could be taken as early as from week 8 + 0, without compromising the excellent performance of the Combined Test. This "Consecutive Combined Test" allows for a centralised laboratory function.METHODS: Inclusion criteria were maternal age > 35 years (80%) or a family history (20%). Double test was taken at a median gestational age (GA) = 10 weeks. NT was measured at GA = 11 + 0 - 13 + 6. A combined risk estimate of > 1:400 at birth was used as cut-off.RESULTS: 881 had the full test. Screen positive = 34. CVS with aneuploidy = 11 (6 trisomy-21, 5 others). FPR = 3.2%. Positive Predictive Value (PPV) = 17.6% for T-21.CONCLUSION: The "Consecutive Combined Test" applied on a high-risk population seems to be highly efficient with a remarkably high PPV.

KW - Adult

KW - Aneuploidy

KW - Chorionic Gonadotropin, beta Subunit, Human/blood

KW - Down Syndrome/diagnosis

KW - Female

KW - Fetal Diseases/diagnosis

KW - Humans

KW - Maternal Age

KW - Nuchal Translucency Measurement

KW - Pregnancy

KW - Pregnancy Trimester, First

KW - Pregnancy-Associated Plasma Protein-A/analysis

KW - Prenatal Diagnosis/methods

U2 - 10.1002/pd.1487

DO - 10.1002/pd.1487

M3 - Journal article

C2 - 17042034

SN - 0197-3851

VL - 26

SP - 1105

EP - 1109

JO - Prenatal Diagnosis

JF - Prenatal Diagnosis

IS - 12

ER -