Folate and prevention of neural tube defectsBMJ 2014; 349 doi: http://dx.doi.org/10.1136/bmj.g4810 (Published 29 July 2014) Cite this as: BMJ 2014;349:g4810
- Robert Clarke, reader in epidemiology and public health medicine,
- Derrick Bennett, senior statistician
- 1Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford OX3 7LF, UK
- Correspondence to: R Clarke
Neural tube defects are the most common disabling birth defect and can be reduced by 80% if women of childbearing age consume 400 µg of folic acid daily.1 In the United Kingdom, where roughly 800 pregnancies are affected each year, the Scientific Advisory Committee on Nutrition recommends that all women planning pregnancy should take 400 μg folic acid daily as a supplement before conception and until the 12th week of pregnancy (or 5 mg daily for women with a previous pregnancy affected by a neural tube defect).1 As half of all pregnancies are unplanned and less than a third of all women start taking folic acid before becoming pregnant,2 voluntary folic acid fortification has been permitted in the United Kingdom (and elsewhere in most European countries), and mandatory fortification has been implemented in North America, South America, and Australia 1. The relative efficacy and safety of voluntary and mandatory folic acid fortification programmes are uncertain.
The study reported by Crider and colleagues in The BMJ (doi:10.1136/bmj.g4554) was designed …