Combined test + inhibin A at week 13 in contingent sequential testing: an interesting alternative for first-trimester prenatal screening for Down syndrome.

摘要: Objective To analyze various possibilities of using dimeric inhibin A (DIA) as a first-trimester marker, during week 13, for diverse sequential strategies together with the combined test (CT) [which uses pregnancy-associated plasma protein A, free beta-human chorionic gonadotrophin and nuchal translucency]. Method We analyzed three (nondisclosure, stepwise contingent) measuring DIA in 13. Multivariate Gaussian modelling was used to estimate second-trimester, false-positive detection rates. Model parameters were taken from Serum, Urine Ultrasound Screening Study (SURUSS) assay. Results The provided high comparable levels effectiveness, rate fixed 85% 5% values about 91 2%, respectively. The contingent strategy (with two CT risk cutoffs, 1 50 2000) produced screening-positive 0.8% CT, while only 23% women needed subsequent measurement. Conclusions First-trimester screening measurement 13 is capable producing results that are those integrated test, additional advantage final result obtained earlier. It recommended this be evaluated large-scale prospective studies. Copyright © 2008 John Wiley & Sons, Ltd.