Second-trimester unconjugated oestriol levels in maternal serum from chromosomally abnormal pregnancies using an optimized assay.
Second-trimester unconjugated oestriol (UE3) levels were measured retrospectively in maternal serum from 78 chromosomally abnormal pregnancies and 390 matched controls using a radioimmunoassay kit (Amersham AMERLEX-M) optimized for use in the second trimester. Reduced levels of UE3 were found in a group of 49 Down's syndrome pregnancies with a median UE3 level of 0.79 multiples of the median (MOM) of the controls. Four trisomy 18 pregnancies had UE3 levels less than 0.7 MOM. There was a highly significant level of correlation between alpha-fetoprotein (AFP) and UE3 levels in the controls (r = 0.25, p < 0.01), the Down's syndrome pregnancies (r = 0.44, p < 0.01), and the other chromosome abnormalities (r = 0.61, p < 0.01). When used as an additional marker to AFP and human chorionic gonadotrophin in screening for Down's syndrome, UE3 does not appear to add to the sensitivity of such screening.
Crossley
J A
JA
Duncan Guthrie Institute of Medical Genetics, Yorkhill, Glasgow, U.K.
Aitken
D A
DA
Connor
J M
JM
D002869:Chromosome Aberrations / Q000097:blood*; D025063:Chromosome Disorders; D002887:Chromosomes, Human, Pair 18; D004314:Down Syndrome / Q000097:blood; D004964:Estriol / Q000097:blood*; D005260:Female; D006801:Humans; D011247:Pregnancy / Q000097:blood*; D011262:Pregnancy Trimester, Second; D011863:Radioimmunoassay; D012189:Retrospective Studies; D014314:Trisomy; D000509:alpha-Fetoproteins / Q000032:analysis
D000509:alpha-Fetoproteins; D004964:Estriol