a total of 3,404 cases of neural tube defects were recorded , among which there were 1,891 cases of anencephaly ( 55.6 % ) , 1,050 cases of spina bifida ( 30.9 % ) and 463 cases of encephalocele ( 13.6 % ) .
C0027794
neural tube defects
C0002902
anencephaly