Double-blind randomised controlled trial of folate treatment before conception to prevent recurrence of neural-tube defects

Br Med J (Clin Res Ed). 1981 May 9;282(6275):1509-11. doi: 10.1136/bmj.282.6275.1509.


A randomized controlled double-blind trial was undertaken in south Wales to prevent the recurrence of neural-tube defects in women who had had one child with a neural-tube defect. Sixty women were allocated before conception to take 4 mg of folic acid a day before and during early pregnancy and 44 complied with these instructions. Fifty-one women were allocated to placebo treatment. There were no recurrences among the compliant mothers but two among the non-compliers and four among the women in the placebo group. Thus there were no recurrences among those who received supplementation and six among those who did not; this difference is significant (p = 0.04). It is concluded that folic acid supplementation might be a cheap, safe, and effective method of primary prevention of neural-tube defects but that this must be confirmed in a large, multicentre trial.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Clinical Trials as Topic
  • Diet
  • Double-Blind Method
  • Female
  • Fertilization*
  • Folic Acid / blood
  • Folic Acid / therapeutic use*
  • Humans
  • Neural Tube Defects / prevention & control*
  • Pregnancy
  • Random Allocation
  • Recurrence


  • Folic Acid