Second trimester maternal dimeric inhibin-A in the multiple-marker screening test for Down's syndrome.
The aim of this study was to evaluate the additional value of dimeric inhibin-A serum concentration in second trimester multiple-marker screening tests for pregnancies affected by Down's syndrome. We anticipated that second trimester maternal serum dimeric inhibin-A concentrations would be altered in pregnancies complicated by fetal Down's syndrome and that dimeric inhibin-A would perform better than one of the three substances analysed in the multiple-marker screening test currently in use. A total of 1156 serum samples were screened for dimeric inhibin-A in parallel with the routine classic triple test screening programme performed on a random obstetric population. Classic triple test performance was compared with detection rates obtained after substitution of unconjugated oestriol by inhibin-A and with the performance of inhibin-A and alpha-fetoprotein alone. Absolute dimeric inhibin-A maternal serum concentrations of Down's syndrome pregnancies were indeed significantly higher than those of normal pregnancies in our screened population. The performance of dimeric inhibin-A in combination with the multiple-marker screening test, however, is limited because of its strong correlation with intact human chorionic gonadotrophin.
Renier
M A
MA
University Hospital of Antwerp, Department of Obstetrics and Gynecology, University of Antwerp, Belgium.
Vereecken
A
A
Van Herck
E
E
Straetmans
D
D
Ramaekers
P
P
Buytaert
P
P
D000465:Algorithms; D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D019281:Dimerization; D004314:Down Syndrome / Q000097:blood*; D004964:Estriol / Q000097:blood; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007265:Inhibins / Q000097:blood*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis; D012016:Reference Values; D000509:alpha-Fetoproteins / Q000032:analysis
D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D000509:alpha-Fetoproteins; D007265:Inhibins; D004964:Estriol