levels of folate , vitamin b12 , the vitamin b12 binding proteins , apotranscobalamin i , ii and iii ( tc i , ii and iii ) and the unsaturated vitamin b12 binding capacity ( ubbc ) were measured in mid-trimester amniotic fluids from normal pregnancies , and from those where the fetus had open spina bifida , anencephaly or omphalocoele , and where the fetus was normal but the mother had had a previous neural tube defect pregnancy .
C0002902
anencephaly
C0027794
neural tube defect