6Sheiner E, et al. Matrnal factors associated with severity of birth defects[ J]. Int J Gynecol Obster, 1999,64:227 - 232.
7Soothill PW, Ajayi RA, Campbell S, et al. Prediction of morbidity in small and normally grown fetuses by fetal heart radiability, biophysical profile score and umbilical artery Doppler studies [ J ]. Br J Obstet Gyhaecol, 1993,100( 8 ) :742 - 749.
8Brar HS, Plart LD. Reverse end - diastolic flow velocity on umbilical artery velocimetry in high - risk pregnancies : an on inous finding with adverse pregnance [ J ]. An J Obstet Gynecol, 1988,159 (10) : 559.
10Zopi MA,lbba RM,Floris M et al.Nuchal translucency measurement at different crow-rump lengths along the 10-to14-week period for Down syndrome screening.Prenat Diagn,2005,25 (5):411～416
