Second-trimester dimeric inhibin-A in Down's syndrome screening

摘要: Initial studies of immunoreactive inhibin using a commercial assay have shown levels to be increased in three second-trimester series maternal samples from Down's syndrome-affected pregnancies. This detected non-specifically all forms circulating inhibin, dimeric and free alpha subunits, whether fully or partially processed. More recently, new specific for inhibin-A has elevated results both first-trimester cases. In order assess the value as potential marker second trimester, we analysed 157 syndrome cases used 367 unaffected across gestational range 14-20 weeks establish control medians population parameters. our series, median MOM was 1.77, significantly higher than controls. At 5 per cent false-positive rate, alone identified 37 When conjunction with age other combinations, mathematical modelling showed detection rates rising 48 (inhibin-A plus age) 61 (inhibin-A, beta hCG, 68 AFP, age). Our data suggest that may greater earlier gestation when at 14-16 are 1.92 compared 1.46 17-23 weeks. Dimeric valuable addition screening protocols, particularly early gestations.