OBJECTIVE: The objective of this study was to determine trends in prenatal detection and current estimates of prevalence for trisomies 18 (T18) and 13 (T13) and their implications for screening policy. METHODS: We conducted a cohort study from a population-based regional anomaly register covering 995 003 births (1995-2009). RESULTS: There were 786 affected cases. Total prevalence of T18 increased from 3.95 in 1995-1999 to 6.94 per 10 000 births in 2005-2009 (annual trend χ(2) = 25.99, p < 0.001) and live birth prevalence, when adjusted for in utero attrition, increased from 1.47 to 2.30 per 10 000 births over the same time (annual trend χ(2) = 6.36, p = 0.01). For T18 and T13 combined, the proportion of cases diagnosed by prenatal karyotype or suspected by ultrasound increased from 85.1% (165/194) in 1995-1999 to 95.2% (299/314) in 2005-2009 (p < 0.001). In 2005-2009, 50.3% of prenatal cytogenetic diagnoses for T18 and 38.5% of T13 were made after the discovery of first trimester ultrasound anomalies, and the majority, 56.4% (185/328), of affected pregnancies were karyotyped or had ended before 18 weeks. CONCLUSION: T18 is increasing in prevalence because of maternal age and earlier surveillance. Prenatal diagnosis occurs mostly in the first trimester, without the intrinsic structures of a formal screening programme. These findings support the extension of first trimester combined screening to include T18 and T13.
OBJECTIVE: The objective of this study was to determine trends in prenatal detection and current estimates of prevalence for trisomies 18 (T18) and 13 (T13) and their implications for screening policy. METHODS: We conducted a cohort study from a population-based regional anomaly register covering 995 003 births (1995-2009). RESULTS: There were 786 affected cases. Total prevalence of T18 increased from 3.95 in 1995-1999 to 6.94 per 10 000 births in 2005-2009 (annual trend χ(2) = 25.99, p < 0.001) and live birth prevalence, when adjusted for in utero attrition, increased from 1.47 to 2.30 per 10 000 births over the same time (annual trend χ(2) = 6.36, p = 0.01). For T18 and T13 combined, the proportion of cases diagnosed by prenatal karyotype or suspected by ultrasound increased from 85.1% (165/194) in 1995-1999 to 95.2% (299/314) in 2005-2009 (p < 0.001). In 2005-2009, 50.3% of prenatal cytogenetic diagnoses for T18 and 38.5% of T13 were made after the discovery of first trimester ultrasound anomalies, and the majority, 56.4% (185/328), of affected pregnancies were karyotyped or had ended before 18 weeks. CONCLUSION: T18 is increasing in prevalence because of maternal age and earlier surveillance. Prenatal diagnosis occurs mostly in the first trimester, without the intrinsic structures of a formal screening programme. These findings support the extension of first trimester combined screening to include T18 and T13.
Authors: Nitin Goel; Joan K Morris; David Tucker; Hermien E K de Walle; Marian K Bakker; Vijaya Kancherla; Lisa Marengo; Mark A Canfield; Karin Kallen; Nathalie Lelong; Jorge L Camelo; Erin B Stallings; Abbey M Jones; Amy Nance; My-Phuong Huynh; Maria-Luisa Martínez-Fernández; Antonin Sipek; Anna Pierini; Wendy N Nembhard; Dorit Goetz; Anke Rissmann; Boris Groisman; Leonora Luna-Muñoz; Elena Szabova; Serhiy Lapchenko; Ignacio Zarante; Paula Hurtado-Villa; Laura E Martinez; Giovanna Tagliabue; Danielle Landau; Miriam Gatt; Saeed Dastgiri; Margery Morgan Journal: Am J Med Genet A Date: 2019-09-30 Impact factor: 2.802
Authors: Robert E Meyer; Gang Liu; Suzanne M Gilboa; Mary K Ethen; Arthur S Aylsworth; Cynthia M Powell; Timothy J Flood; Cara T Mai; Ying Wang; Mark A Canfield Journal: Am J Med Genet A Date: 2015-12-10 Impact factor: 2.802
Authors: Cara T Mai; Jennifer L Isenburg; Mark A Canfield; Robert E Meyer; Adolfo Correa; Clinton J Alverson; Philip J Lupo; Tiffany Riehle-Colarusso; Sook Ja Cho; Deepa Aggarwal; Russell S Kirby Journal: Birth Defects Res Date: 2019-10-03 Impact factor: 2.661