Folic acid supplements in pregnancy and birth outcome: re-analysis of a large randomised controlled trial and update of Cochrane review
Article first published online: 22 MAR 2005
Paediatric and Perinatal Epidemiology
Volume 19, Issue 2, pages 112–124, March 2005
How to Cite
Charles, D. H. M., Ness, A. R., Campbell, D., Smith, G. D., Whitley, E. and Hall, M. H. (2005), Folic acid supplements in pregnancy and birth outcome: re-analysis of a large randomised controlled trial and update of Cochrane review. Paediatric and Perinatal Epidemiology, 19: 112–124. doi: 10.1111/j.1365-3016.2005.00633.x
- Issue published online: 22 MAR 2005
- Article first published online: 22 MAR 2005
Periconceptual folic acid prevents neural tube defects. The effect of folic acid taken throughout pregnancy is unclear, however. We re-analysed data from a large randomised controlled trial performed between 1966 and 1967 and combined the results with those from trials included in a Cochrane review. A total of 2928 women were randomised: 1977 were allocated to placebo, 466 to folic acid 200 µg/day and 485 to folic acid 5 mg/day.
Folic acid supplementation was not associated with any difference in mean birthweight, placental weight or gestational age. When combined with trials in the Cochrane review folic acid at high doses was associated with reduced risk of low birthweight (pooled relative risk 0.73 [95% CI 0.53, 0.99]). We found no conclusive evidence of benefit for folic acid supplementation in pregnant women given from time of booking onwards.