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RCOG statement: Study claims too much folate can increase autism risk

News 12 May 2016

New research from the Johns Hopkins Bloomberg School of Public Health suggests there could be an increased risk of autism in children of mothers who have too much folate. 

Professor Richard Anderson, spokesperson for the Royal College of Obstetricians and Gynaecologists (RCOG), said:

“There is strong scientific evidence showing that folic acid reduces the number of pregnancies affected by neural tube defects, such as spina bifida. The RCOG, with health authorities around the world, recommends that women take folic acid when trying to conceive and in early pregnancy. In this new study women taking low doses of folic acid supplements were less likely to have a child with autism, but those with very high levels of folic acid in their blood were more likely to have a child with autism. The authors of the study acknowledge the well-established health benefits of folic acid supplements, and do not suggest that women stop taking folic acid supplements.

“The results of this small study should be treated with caution as any mechanism linking folic acid with autism remains unknown. However it highlights that women should take the recommended daily intake, but not exceed it. The causes of autism remain an important area of research.

“The RCOG recommends that all women take 400 micrograms of folic acid daily while they are trying to conceive, and until their 12th week of pregnancy, with higher doses only recommended for certain groups of women such as those with diabetes. We are also calling for a food fortification policy with mandatory fortification of bread or flour with folic acid as a public health measure to prevent folate deficiency and to improve the lives of both mothers and babies. This will reach women most at risk due to poor dietary habits or socioeconomic status, in addition to those women who may not have planned their pregnancy.”


For media enquiries, please contact the RCOG press office on 020 772 644/357 or email