EP06.18: Current prenatal screening efficacy of Trisomy 21, 18 13 in the Taiwan: a 6‐year national registry study

Abstract

To evaluate of the prenatal screening efficacy of Trisomy 21, 18 13 in the Taiwan. This was a national registry-based cohort study, the total 1,218,851 baby births since January 2010 to December 2015. The current prenatal screening methods including the first trimester combined test, the secondary trimester quadruple and double serum test in Taiwan. The indication of prenatal cytogenetic diagnosis including: advanced maternal age (35 years and older at expected time of delivery), abnormal first trimester combined or second trimester serum screening risk higher than 1/270 on the basis both of tests, ultrasound scan abnormalities suggestive of a chromosomal abnormality, neural tube defect or elevated MS-AFP, parents with chromosomal balanced rearrangements, previous baby with chromosomal or congenital abnormality, have family history of DNA abnormality or metabolic disorder, and miscellaneous. Personal registration numbers of women having had an amniocentesis or a CVS were retrieved from the Taiwan Central Cytogenetic Registry, and cross-linked with the National Registry of Patients to determine the outcome of each pregnancy. We estimated the total invasive prenatal diagnosis was 299,917 (amniocentesis n=298,063; chorionic villus sampling n=1,604; cordocentesis n=238), and the overall invasive procedure rate was 24.59%. The population prevalence in Trisomy 21, 18, and 13 is one in 624, 2232, and 8055 respectively. The prenatal detection Trisomy 21, 18, and 13 had 1794, 534, and 145 cases and had 156, 11, and 6 cases live born respectively. The overall detection rate was one in 92.0%, 98.0%, and 96.0% respectively. The overall detection rate is high than 92%, which is related too high invasive procedure rate. It may adjust the indications strategy to reduce the invasive prenatal diagnosis rate to prevent collateral damage.