INTRODUCTION: First trimester screening (FTS) is a validated screening tool that has been shown to achieve detection rates of 84%-90% for trisomies 21, 18 and 13. However, its effectiveness for different maternal ages has not been assessed. The present study aimed to assess the performance of FTS in an Asian population, and to compare its effectiveness in older (≥ 35 years) and younger (< 35 years) women. The potential use of noninvasive prenatal test (NIPT) as a contingent screening test is also examined. METHODS: Data on cases of FTS performed on singleton pregnancies over a six-year period was collated from two Singapore maternal centres, National University Hospital and Singapore General Hospital. Cases that had a 1:250 risk of trisomy were considered to be screen-positive. Pregnancy outcomes were obtained from birth records or karyotype test results. RESULTS: From 10,289 FTS cases, we obtained a sensitivity of 87.8%, a specificity of 97.6%, a false positive rate of 2.4% and a false negative rate of 0.06% for the detection of aneuploidy. The overall detection rate for trisomy 21 was 86.5%-85.7% for older women and 87.5% for younger women. The mean number of invasive tests required per case of trisomy 21 was 9.3 in younger women, 8.6 in older women and 13.5 in women with intermediate risk (1:250-1,000). CONCLUSION: While the performance of FTS was similar in younger and older women, more invasive procedures were required to diagnose trisomy 21 in women with intermediate risk. It may be advantageous to offer contingent NIPT to this group of women to reduce the risk of iatrogenic fetal loss.
INTRODUCTION: First trimester screening (FTS) is a validated screening tool that has been shown to achieve detection rates of 84%-90% for trisomies 21, 18 and 13. However, its effectiveness for different maternal ages has not been assessed. The present study aimed to assess the performance of FTS in an Asian population, and to compare its effectiveness in older (≥ 35 years) and younger (< 35 years) women. The potential use of noninvasive prenatal test (NIPT) as a contingent screening test is also examined. METHODS: Data on cases of FTS performed on singleton pregnancies over a six-year period was collated from two Singapore maternal centres, National University Hospital and Singapore General Hospital. Cases that had a 1:250 risk of trisomy were considered to be screen-positive. Pregnancy outcomes were obtained from birth records or karyotype test results. RESULTS: From 10,289 FTS cases, we obtained a sensitivity of 87.8%, a specificity of 97.6%, a false positive rate of 2.4% and a false negative rate of 0.06% for the detection of aneuploidy. The overall detection rate for trisomy 21 was 86.5%-85.7% for older women and 87.5% for younger women. The mean number of invasive tests required per case of trisomy 21 was 9.3 in younger women, 8.6 in older women and 13.5 in women with intermediate risk (1:250-1,000). CONCLUSION: While the performance of FTS was similar in younger and older women, more invasive procedures were required to diagnose trisomy 21 in women with intermediate risk. It may be advantageous to offer contingent NIPT to this group of women to reduce the risk of iatrogenic fetal loss.
Authors: Tak Yeung Leung; Lin Wai Chan; Lai Wa Law; Daljit Singh Sahota; Tak Yuen Fung; Tse Ngong Leung; Tze Kin Lau Journal: J Matern Fetal Neonatal Med Date: 2009-04
Authors: Mary E Norton; Herb Brar; Jonathan Weiss; Ardeshir Karimi; Louise C Laurent; Aaron B Caughey; M Hellen Rodriguez; John Williams; Michael E Mitchell; Charles D Adair; Hanmin Lee; Bo Jacobsson; Mark W Tomlinson; Dick Oepkes; Desiree Hollemon; Andrew B Sparks; Arnold Oliphant; Ken Song Journal: Am J Obstet Gynecol Date: 2012-06-01 Impact factor: 8.661
Authors: Diana W Bianchi; Lawrence D Platt; James D Goldberg; Alfred Z Abuhamad; Amy J Sehnert; Richard P Rava Journal: Obstet Gynecol Date: 2012-05 Impact factor: 7.661
Authors: Rossa W K Chiu; Ranjit Akolekar; Yama W L Zheng; Tak Y Leung; Hao Sun; K C Allen Chan; Fiona M F Lun; Attie T J I Go; Elizabeth T Lau; William W K To; Wing C Leung; Rebecca Y K Tang; Sidney K C Au-Yeung; Helena Lam; Yu Y Kung; Xiuqing Zhang; John M G van Vugt; Ryoko Minekawa; Mary H Y Tang; Jun Wang; Cees B M Oudejans; Tze K Lau; Kypros H Nicolaides; Y M Dennis Lo Journal: BMJ Date: 2011-01-11