Comparison of urinary free beta (hCG) and beta-core (hCG) in prenatal screening for chromosomal abnormalities.
To evaluate the potential utility of free beta (hCG) and beta-core (hCG) in a prenatal screening protocol for Down syndrome we analysed these markers in dried maternal urine specimens from 163 control, 13 Down syndrome and 5 trisomy 18 pregnancies from 8 to 25 weeks' gestation. All results are reported after normalization for urinary creatinine determined by modified Jaffe reagent assay. The correlation of urinary free beta (hCG) and urinary beta-core (hCG) was 0.61 in controls and 0.93 in Down syndrome. Median MoM values in Down syndrome were 2.42 for urinary free beta (hCG) and 2.40 for beta-core (hCG). In trisomy 18 the Median MoM was 0.35 and 0.34 for free beta (hCG) and beta-core (hCG), respectively. The degree of elevation observed in DS cases with urinary free beta (hCG) is consistent with previous reports. Studies of beta-core (hCG) in Down syndrome have yielded discrepant results. In this study, beta-core (hCG) in Down syndrome is lower than values observed in early reports but consistent with more recent reports.
Hallahan
T W
TW
Research Division, NTD Laboratories, Inc., Huntington Station, NY 11746, USA.
Krantz
D A
DA
Tului
L
L
Alberti
E
E
Buchanan
P D
PD
Orlandi
F
F
Klein
V
V
Larsen
J W
JW
Macri
J N
JN
D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000652:urine*; D002869:Chromosome Aberrations; D002887:Chromosomes, Human, Pair 18; D004314:Down Syndrome / Q000175:diagnosis*; D005189:False Positive Reactions; D005260:Female; D005865:Gestational Age; D006801:Humans; D010209:Paper; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012016:Reference Values; D014314:Trisomy
D018997:Chorionic Gonadotropin, beta Subunit, Human