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

TLDR

A double‑blind randomized trial in south Wales assigned 60 women to 4 mg folic acid before and during early pregnancy and 51 to placebo, with 44 women complying with the supplementation. Supplementation prevented all neural‑tube defect recurrences, with six cases in the non‑supplemented group versus none in the supplemented group (p = 0.04), suggesting folic acid is a cheap, safe, and potentially effective primary prevention strategy that warrants confirmation in larger trials.

Abstract

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.