Folic Acid Supplementation & Neural Tube Defects

Abundant scientific evidence has shown a link between maternal folic acid deficiency during early pregnancy and the development of neural tube defects in the fetus. The American Academy of Pediatrics recommends that “all women of childbearing age who are capable of becoming pregnant should consume 400 micrograms of folic acid daily.” For women who have had a child with a neural tube defect and women who themselves have a neural tube defect, the American Academy of Pediatrics recommends “4000 micrograms of folic acid per day starting 1 month before the time they plan to become pregnant and throughout the first 3 months of pregnancy, unless contraindicated.” For further details, please see Neural Tube Defects - AAP Policy Statement on Folic Acid Supplementation.
Although folic acid supplementation has decreased the incidence of neural tube defects in the United States from 25% to 45%, clearly, other factors are also important. [Jägerstad: 2012] In one area of the country, these included obesity, high-serum homocysteine levels, low-serum B12 levels, stress, and exposure to fumonisins, which are fungi produced toxins in corn grain. [Suarez: 2012] Genetic mechanisms are also likely involved. [Dupépé: 2017]


Practice Guidelines

The following provides guidance on folic acid supplementation.

Cheschier N.
ACOG practice bulletin. Neural tube defects. Number 44, July 2003. (Replaces committee opinion number 252, March 2001).
Int J Gynaecol Obstet. 2003;83(1):123-33. PubMed abstract

Helpful Articles

Chitayat D, Matsui D, Amitai Y, Kennedy D, Vohra S, Rieder M, Koren G.
Folic acid supplementation for pregnant women and those planning pregnancy: 2015 update.
J Clin Pharmacol. 2016;56(2):170-5. PubMed abstract / Full Text

Authors & Reviewers

Initial publication: January 2013; last update/revision: November 2019
Current Authors and Reviewers:
Authors: Lynne M. Kerr, MD, PhD
Margaret Braae, RD
Authoring history
2013: first version: Lynne M. Kerr, MD, PhDA; Margaret Braae, RDA
AAuthor; CAContributing Author; SASenior Author; RReviewer

Page Bibliography

Dupépé EB, Patel DM, Rocque BG, Hopson B, Arynchyna AA, Bishop ER, Blount JP.
Surveillance survey of family history in children with neural tube defects.
J Neurosurg Pediatr. 2017;19(6):690-695. PubMed abstract / Full Text

Jägerstad M.
Folic acid fortification prevents neural tube defects and may also reduce cancer risks.
Acta Paediatr. 2012;101(10):1007-12. PubMed abstract

Suarez L, Felkner M, Brender JD, Canfield M, Zhu H, Hendricks KA.
Neural tube defects on the Texas-Mexico border: what we've learned in the 20 years since the Brownsville cluster.
Birth Defects Res A Clin Mol Teratol. 2012;94(11):882-92. PubMed abstract