2Clementi M,Tenconi R,Bianchi F,et al.Evaluation of prenatal diagnosis of cleft lip or without cleft palate by ultrasound:ex-perience from 20 Europpean registries.Prenat Diagn,2000,20:870-875.
3Cash C,set P,Coleman N.The accuracy of antenatal ultrasound in the detection of facial clefts in a low-risk screening population.Ultrasound Obstet Gynecol,2001,18:432-436.
