6Cuneo BF,Curran LF,Davis N,et al. Trends in prenatal diagnosis of critical cardiac defects in an integrated obstetric and pediatric cardiac imaging center[J]. J Perinatol,2004,24:674-678.
7Hyett J, Perdu M, Sharland G, et al. Using fetal nuchal translucency to screen for major congenital cardiac defects at 10-14 weeks of gestation : population based cohort study [ J ]. BMJ, 1999,318:81-85.
8Haak MC, Twisk JWR, van Vugt JMG. How successful is fetal echocardiographic examination in the first trimester of pregnancy [J]. Ultrasound Obstet Gynecol,2002 ,20 :9-13.
9Chaoui R. The four-chamber view: four reasons why it seems to fail in screening for cardiac abnormalities and suggestions to improve detection rate [ J ]. Ultresound Obstet Gynecol, 2003,22 (1) :3-10.
10Yagel S, Arbel R, Anteby EY, et al. Three vessels and trachea view (3VT) in fetal cardiac scanning[J]. Ultrasound Obstet Gynecol,2002,20 (4) : 340-345.
3Botto LD, May K, Fernhoff PM, et al. A population-based studyof the 22ql 1. 2 deletion : phenotype, incidence, and contri-bution to major birth defects in the population [ J ]. Pediatrics,2003,112(1) :101 -107.