MATERNAL SERUM MARKERS - ESTIMATION OF THE RISK OF DOWNS-SYNDROME - APROSPECTIVE-STUDY

The risk of Down's syndrome pregnancies can be estimated by quantitati on of maternal serum markers, namely alpha-fetoprotein, unconjugated e striol and human chorionic gonadotropin (triple test). A prospective s tudy of 2892 pregnant women (median age 33.5 years) is reported. The d etection rate of Down's syndrome pregnancies was 80% (confidence inter vals 45%-100%) when a risk of 1:380 or greater was considered ''screen positive''; the false positive rate was 13.3% (confidence intervals 1 2.0%-14.5%). The importance of the accurate assessment of gestational age and the time of blood sampling are emphasized. Our findings are co mpared with similar studies performed in other laboratories.