[Value of immunoassay of hCG for the determination of high plasma concentrations].

The serum concentration of human chorionic gonadotrophin is higher in trisomy 21 than in normal pregnancy. Our study aimed at comparing 17 commercial kits, both those for measuring high concentrations and others for diagnosis and initial follow-up of pregnancy under specific conditions, ie for measuring hCG concentrations between weeks 14 and 18 of pregnancy. All kits were satisfactory; however, usual values for the gestational weeks concerned need to be established for each reagent.