Current Treatment Options in Neurology

, Volume 2, Issue 2, pp 117–122

Birth defects and supplemental vitamins

  • Marvin A. Fishman

Opinion statement

  • Women of childbearing age who are capable of becoming pregnant should ingest 0.4 mg of folic acid per day to reduce the incidence of neural tube defects (anencephaly, spina bifida, and encephalocele). This may also reduce the incidence of conotruncal heart defects, limb defects, renal anomalies, pyloric stenosis, and possibly oral-facial clefts.

  • Women who are at increased risk of having an affected fetus because of having had a previously affected fetus should take 4 mg of folic acid daily.

  • Women with epilepsy, particularly those taking antiepileptic drugs, should follow the same guidelines as nonepileptic women; however, women with epilepsy should take the lowest dose and the fewest number of antiepileptic drugs needed to control the epilepsy.

  • Physicians and the public should be educated about the benefits of supplemental folic acid and the consumption of folate-rich foods and fortified foods in reducing the incidence of neural tube defects and other congenital anomalies. They should be made aware that neural tube defects occur between 23 and 28 days of gestation, often before women know they are pregnant. Therefore, folic acid supplements need to be taken at least 1 month before the beginning of pregnancy. Because many pregnancies are unplanned, women should take folic acid supplements routinely.


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References and Recommended Reading

  1. 1.
    Hall JG, Solehdin F: Folate and its various ramifications. Adv Pediatr 1998, 45:1–35. Excellent review of the subject. There are discussions of folate metabolism and consumption and strategies for increasing its intake. Background studies of the prevention of birth defects are reviewed.PubMedGoogle Scholar
  2. 2.
    Molloy AM, Mills JL, Kirke PN, et al.: Low blood folates in NTD pregnancies are only partly explained by thermolabile 5,10-methylenetetrahydrofolate reductase: low folate status alone may be the critical factor. Am J Med Genet 1998, 78:155–159.PubMedCrossRefGoogle Scholar
  3. 3.
    MRC Vitamin Study Research Group: Prevention of neural tube defects: results of the Medical Research Council vitamin study. Lancet 1991, 338:131–137. Landmark study demonstrating the effectiveness of folic acid supplementation in preventing recurrence of neural tube defects.CrossRefGoogle Scholar
  4. 4.
    Czeizel AE, Dudas I: Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med 1992, 327:1832–1835. Landmark study demonstrating the effectiveness of folic acid in preventing the first-time occurrence of neural tube defects.PubMedCrossRefGoogle Scholar
  5. 5.
    Hall J, Solehdin F: Folic acid for the prevention of congenital anomalies. Eur J Pediatr 1998, 157:445–450. Discusses public health recommendations and previous attempts at educating the public regarding the benefits of folic acid consumption.PubMedCrossRefGoogle Scholar
  6. 6.
    Butterworth CE Jr, Bendich A: Folic acid and the prevention of birth defects. Annu Rev Nutr 1996, 16:73–97. Good general review of the topic.PubMedCrossRefGoogle Scholar
  7. 7.
    Locksmith GJ, Duff P: Preventing neural tube defects: the importance of periconceptional folic acid supplements. Obstet Gynecol 1998, 91:1027–1034.PubMedCrossRefGoogle Scholar
  8. 8.
    Daly S, Mills JL, Molloy AM, et al.: Minimum effective dose of folic acid for food fortification to prevent neural-tube defects. Lancet 1997, 350:1666–1669.PubMedCrossRefGoogle Scholar
  9. 9.
    Daly S, Scott JM: The prevention of neural tube defects. Curr Opin Obstet Gynecol 1998, 10:85–89.PubMedCrossRefGoogle Scholar
  10. 10.
    Jacques PF, Selhub J, Bostom AG, et al.: The effect of folic acid fortification on plasma folate and total homocysteine concentrations. N Engl J Med 1999, 340:1449–1454.PubMedCrossRefGoogle Scholar
  11. 11.
    Czeizel AE: Prevention of congenital abnormalities by periconceptional multivitamin supplementation. BMJ 1993, 306:1645–1648. Study demonstrating the benefits of folic acid supplementation in preventing birth defects other than neural tube defects.PubMedCrossRefGoogle Scholar
  12. 12.
    Czeizel AE: Nutritional supplementation and prevention of congenital abnormalities. Curr Opin Obstet Gynecol 1995, 7:88–94.PubMedGoogle Scholar
  13. 13.
    Czeizel AE: Periconceptional folic acid-containing multivitamin supplementation. Eur J Obstet Gynecol Reprod Biol 1998, 78:151–161.PubMedCrossRefGoogle Scholar
  14. 14.
    Morrell MJ: Guidelines for the care of women with epilepsy. Neurology 1998, 51(suppl 4):S21-S27.PubMedGoogle Scholar
  15. 15.
    Lindhout D, Omtzigt JGC: Teratogenic effects of antiepileptic drugs: implications for the management of epilepsy in women of childbearing age. Epilepsia 1994, 35(suppl 4):S19-S28.PubMedGoogle Scholar
  16. 16.
    Lewis DP, Van Dyke DC, Stumbo PJ, et al.: Drug and environmental factors associated with adverse pregnancy outcomes, part I: antiepileptic drugs, contraceptives, smoking, and folate. Ann Pharmacother 1998, 32:802–817. Discusses the correlation between peak serum valproic acid concentration and neural tube defects.PubMedCrossRefGoogle Scholar

Copyright information

© Current Science Inc 2000

Authors and Affiliations

  • Marvin A. Fishman
    • 1
  1. 1.Neurology ServiceTexas Children’s HospitalHoustonUSA

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