Folate and neural tube defects.

The multifactorial aetiology of neural tube defects has stimulated many theories related to dietary factors in pregnancy. The results of the Medical Research Council Study confirm that folate has a protective effect if taken in the 3 months prior to conception and for the first trimester. The dosage recommended is 5mg daily for women at risk for recurrence of spina bifida or anencephaly and 0.5mg daily for those at low risk. Dietary modification to include foods with high folate such as leafy green vegetables and wholemeal grain is not considered sufficient. Fortification of staple food items such as bread and cereals with folate is being considered in some countries. A comprehensive health education programme is essential, directed to women in the reproductive age group and to doctors involved in primary care, family planning and obstetric management. The incidence of neural tube defects could be reduced by 70% with the introduction of folate supplementation in all pregnancies.