Examples
include low folate intake levels and risk of NTDs was high
in pregnancies from low socio-economic families [41, 42],
mean RBC folate concentrations in women with a NTD was
lower [43], folic acid metabolism in pregnant women affected
by NTD was impaired [44], and the use of aminopterin,
a powerful folic acid antagonist, was associated with anen-
cephaly [45]. These observations have led to large scale
randomized c