Women with pre-gestational diabetes have an increased risk (3-fold) of neural tube defect compared to the babies of mothers in general. (CEMACH- Pregnancy in women with Type 1 and Type 2 diabetes in 2002-2003)
To minimise this risk women with diabetes should take 5mgs daily (ideally for three months before conception) and for the first 12 weeks of pregnancy. This dose of folic acid is only available on prescription.
In the British diet the main sources of folic acid are cereals and green, leafy vegetables. A significant proportion of folic acid is obtained through bread or breakfast cereals fortified with folic acid.
Further information on nutritional guidelines