American Academy of Pediatrics: folic acid for the prevention of neural tube defects. Pediatrics. 1999;104(2):325-327. Statement of reaffirmation published May 1, 2007.

American College of Obstetricians and Gynecologists (ACOG). Neural tube defects. Washington (DC): American College of Obstetricians and Gynecologists (ACOG); 2003 Jul. 11 p. (ACOG practice bulletin; no. 44).

Bentley TG, Willett WC, Weinstein MC, Kuntz KM. Population-level changes in folate intake by age, gender, and race/ethnicity after folic acid fortification. Am J Public Health. 2006;96(11):2040-7.

Bol KA, Collins JS, Kirby RS. Survival of infants with neural tube defects in the presence of folic acid fortification. Pediatrics. 2006;117(3):803-13.

Boulet SL, Yang Q, Mai C, et al. Trends in the postfortification prevalence of spina bifida and anencephaly in the United States. Birth Defects Res A Clin Mol Teratol. 2008;82(7):527-32.

Bukowski R, Malone F, Porter FD, Nyberg DA. Preconceptional folate prevents preterm delivery. Am J Obstet Gynecol. 2007;197:S3.

Cena ER, Joy AB, Heneman K, et al. Learner-centered nutrition education improves folate intake and food-related behaviors in nonpregnant, low-income women of childbearing age. J Am Diet Assoc. 2008;108(10):1627-35.

Czeizel AE, Dudas I. Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med. 1992; 327:1832-35.

Czeizel AE, Laszlo T, Sarkozi A. Dose-dependent effect of folic acid on the prevention of orofacial clefts. Pediatrics. 1999;104(6):e66.

Folate status in women of childbearing age, by race/ethnicity—United States, 1999-2000, 2001-2002, and 2003-2004. MMWR. 2007;55(51):1377-80.

Fruit and vegetable consumption among adults—United States, 2005. MMWR. 2007;56(10):213-17.

Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA. Neural tube defects in relation to use of folic acid antagonists during pregnancy. Am J Epidemiol. 2001;153(10):961-8.

Johnston KE, Tamura T. Folate content in commercial white and whole wheat sandwich breads. J Agric Food Chem. 2004;52(20):6338-40.

Lumley J, Watson L, Watson M, Bower C. Periconceptional supplementation with folate and/or multivitamins for preventing neural tube defects. Cochrane Database Syst Rev 2001;(3):CD001056.

March of Dimes Birth Defects Foundation. (2004, June). Folic acid and the prevention of birth defects: A national survey of prepregnancy awareness and behavior among women of childbearing age 1995–2004. White Plains, NY.

Matthews TJ. Trends in spina bifida and anencephalus in the United States, 1991-2005. National Center for Health Statistics. Centers for Disease Control and Prevention. December, 2007. http://www.cdc.gov/nchs/products/pubs/pubd/hestats/spine_anen.htm.

McDowell MA, Lacher DA, Pfeiffer CM, et al. Blood folate levels: The latest NHANES results. NCHS data briefs, no. 6. Hyattsville, MD: National Center for Health Statistics. 2008.

Milunsky A, Jick H, Jick SS, et al. Multivitamin/folic acid supplementation in early pregnancy reduces the prevalence of neural tube defects. JAMA. 1988; 262:2847-52.

Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group. Lancet. 1991;338(8760):131-7.

Ratan SK, Rattan KN, Prandey RM, et al. Evaluation of the levels of folate, vitamin B12, homocysteine and fluoride in the parents and the affected neonates with neural tube defect and their matched controls. Pediatr Surg Int. 2008;24(7):803-8.

Summary of recommendations for clinical preventive services. Revision 6.8, January 2009. American Academy of Family Physicians. www.aafp.org.

Use of supplements containing folic acid among women of childbearing age-United States, 2007. MMWR. 2008;57(01):5-8.

van Rooij I, Ocke' MC, Straatman H, Zielhuis GA, Merkus H, Steegers-Theunissen R. Periconceptional folate intake by supplement and food reduces the risk of nonsyndromic cleft lip with or without cleft palate. Prev Med. 2004;39:689-94.

Wald NJ, Hackshaw AD, Stone R, Sourial NA. Blood folic acid and vitamin B12 in relation to neural tube defects. Br J Obstet Gynaecol. 1996;103(4):319-24.

Wald NJ, Law MR, Morris JK, Wald DS. Quantifying the effect of folic acid. Lancet. 2001;358:2069-73.

Watkins ML, Brustrom J, Schulman J. Effectiveness of a free folic acid supplement program in family planning clinics. Birth Defects Res A Clin Mol Teratol. 2004;70(6):403-7.

Wilcox AJ, Lie RT, Solvoll K, et al. Folic acid supplements and risk of facial clefts: national population based case-control study. BMJ. 2007;334:464.

Williams LJ, Rasmussen SA, Flores A, Kirby RS, Edmonds LD. Decline in the prevalence of spina bifida and anencephaly by race/ethnicity. Pediatrics. 2005;116(3):580-6.

Yang QH, Carter HK, Mulinare J, Berry RJ, Friedman JM, Erickson JD. Race-ethnicity differences in folic acid intake in women of childbearing age in the United States after folic acid fortification: findings from the National Health and Nutrition Examination Survey, 2001-2002. Am J Clin Nutr. 2007;85(5):1409-16.