Related Experiment Video
Updated: Aug 8, 2026

07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
A single chorionic gonadotropin assay for maternal serum screening for Down's syndrome
Prenatal Diagnosis
|June 1, 1990
Abstract:
A simple enzyme immunoassay measuring human chorionic gonadotropin in undiluted maternal serum has been developed in order to be used as a prenatal screening test for Down's syndrome. A retrospective study of maternal serum sampled during pregnancies associated with trisomy 21 shows that with a 5% amniocentesis rate determined on a single test, the detection rate of trisomy 21 would be around two-thirds of the affected pregnancies. A prospective study of 9040 pregnant women under 38 years has confirmed the usefulness of the assay.
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