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Too Much Folic Acid During Pregnancy May Increase Risk of Autism

Too Much Folic Acid During Pregnancy May Increase Risk of Autism

Folic acid supplementation is an important part of prenatal care. It has been clearly shown to reduce the risk of neural tube defects (such as spina bifida) in a developing fetus. Since the late 1990s, our food supply has been fortified with folic acid and dietary supplementation of folic acid has been routinely recommended prior to and during pregnancy. Scientific research has traditionally focused on the benefits of folic acid supplementation. Recent literature, however, suggests that too much folic acid may be associated with adverse effects on the fetus. In particular, some studies suggest that too much folic acid during pregnancy may increase risk of autism.

As a medical community, we are still investigating this possible association between folate levels and autism. The literature on this subject is confusing, as some studies suggest that folic acid may have a protective effect against autism, while others suggest that folic acid (at high levels) may have a detrimental effect.

How Much Folic Acid is Too Much During Pregnancy?

At this time, we would recommend that patients stay within the recommended dietary allowance (RDA) for folic acid. In general, we recommend 600-800 mcg daily (or the equivalent) for women who are pregnant or trying to conceive. Over-supplementing should be avoided, and the RDA should not exceed 1000 mcg daily unless specifically recommended by the patient’s treating physician. These findings highlight the importance of discussing all medications and supplements with your physician on an ongoing basis.

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At Fertility Centers of New England (FCNE), many patients come to us because they are struggling with infertility and/or miscarriages. We are proud to have helped thousands of patients realize their dream of becoming a parent. We want each of our patients to have the safest, healthiest pregnancy possible.

If you have more questions on how too much folic acid during pregnancy may increase risk of autism, please contact us to schedule your free initial consultation.

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Wiens D, DeSoto MC. Is High Folic Acid Intake a Risk Factor for Autism?-A Review. Brain Sci. 2017 Nov 10;7(11):149.





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