2Johnson SP, Sebire NJ, Snijders R J, et al. Ultrasound screening for anencephaly at 10 - 14 weeks of gestation[ J]. Ultrasound Obstet Gy- necol, 1997 Jan,9( 1 ) : 14 -6.
3Salvador J, Arigita M, Carreras E, et al. Evolution of prenatal detec- tion of neural tube defects in the pregnant population of the city of Barcelona from 1992 to 2006[J]. Prenat Diagn, 2011 Dec,31 (12): 1184 -8.
4严英榴 杨秀雄 沈理.产前超声诊断学[M].北京:人民卫生出版社,2002.332-336.
5Beinder E, Grtiner C, Erhardt I, et al. The exencephaly - anenceph- aly sequence. Ultrasound diagnosis in early pregnancy [ J ]. Ultras- chall Med, 1995 Aug, 16 (4) : 192 - 5.
7Ben- Ami I, Edel Y, Barel O, et al. Do assisted conception twins have an increased risk for anencephaly? [ J ]. Hum Reprod, 2011 Dec,26 (12) : 3466 -71.
4Gardner DK, Lane M. Culture and selection of viable blastocysts: A feasible proposition for human IVF[J]. Hum Reprod Update, 1997,3 (4) :367-382.
5Findlay I. Pre-implantation genetic diagnosis[J]. Br Med Bull,2000, 56(3):672-690.
6Strehler E, Abt M, EI-Danasouri I,et al. Impact of rFSH and hMG on IVF outcome[Jl. Fertil 8tefil, 2001,75(2) :382-336.
7Limb CJ ,Holmes LB.Anencephaly:changes in prenatal detection and birth status,1972through1990.Am J Obstet Gynecol,1994,170(5):1333-1336.
8Chan A,Robertson EF,Haan EA,et al.Prevalence of neural tube defects in South Australia,1966-1991:effectiveness and impact of prenatal diagnosis.Br Med J,1993,307(6906):703-706.
9Chan A,Robertson EF,Haan EA,et al.The sensitivity of ultrasound and serum alpha-fetoprotein in population-based antenatal screening for neural tube defects,South Australia 1986-1991.Br J Obstet Gynecol,1995,102(5):370-374.