title: International retrospective cohort study of neural tube defects in relation to folic acid recommendations: are the recommendations working?
abstract: OBJECTIVE
  To evaluate the effectiveness of policies and recommendations on folic acid aimed at reducing the occurrence of neural tube defects.
  
  
  METHODS
  Retrospective cohort study of births monitored by birth defect registries.
  
  
  METHODS
  13 birth defects registries monitoring rates of neural tube defects from 1988 to 1998 in Norway, Finland, Northern Netherlands, England and Wales, Ireland, France (Paris, Strasbourg, and Central East), Hungary, Italy (Emilia Romagna and Campania), Portugal, and Israel. Cases of neural tube defects were ascertained among liveborn infants, stillbirths, and pregnancy terminations (where legal). Policies and recommendations were ascertained by interview and literature review.
  
  
  METHODS
  Incidences and trends in rates of neural tube defects before and after 1992 (the year of the first recommendations) and before and after the year of local recommendations (when applicable).
  
  
  RESULTS
  The issuing of recommendations on folic acid was followed by no detectable improvement in the trends of incidence of neural tube defects.
  
  
  CONCLUSIONS
  Recommendations alone did not seem to influence trends in neural tube defects up to six years after the confirmation of the effectiveness of folic acid in clinical trials. New cases of neural tube defects preventable by folic acid continue to accumulate. A reasonable strategy would be to quickly integrate food fortification with fuller implementation of recommendations on supplements.
authors.affiliation: National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. icbd@icbd.org
authors.forename: Lorenzo D
authors.initials: LD
authors.lastname: Botto
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lisi
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Robert-Gnansia
authors.forename: J David
authors.initials: JD
authors.lastname: Erickson
authors.forename: Stein Emil
authors.initials: SE
authors.lastname: Vollset
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Mastroiacovo
authors.forename: Beverley
authors.initials: B
authors.lastname: Botting
authors.forename: Guido
authors.initials: G
authors.lastname: Cocchi
authors.forename: Catherine
authors.initials: C
authors.lastname: de Vigan
authors.forename: Hermien
authors.initials: H
authors.lastname: de Walle
authors.forename: Maria
authors.initials: M
authors.lastname: Feijoo
authors.forename: Lorentz M
authors.initials: LM
authors.lastname: Irgens
authors.forename: Bob
authors.initials: B
authors.lastname: McDonnell
authors.forename: Paul
authors.initials: P
authors.lastname: Merlob
authors.forename: Annukka
authors.initials: A
authors.lastname: Ritvanen
authors.forename: Gioacchino
authors.initials: G
authors.lastname: Scarano
authors.forename: Csaba
authors.initials: C
authors.lastname: Siffel
authors.forename: Julia
authors.initials: J
authors.lastname: Metneki
authors.forename: Claude
authors.initials: C
authors.lastname: Stoll
authors.forename: Richard
authors.initials: R
authors.lastname: Smithells
authors.forename: Janine
authors.initials: J
authors.lastname: Goujard
mesh_terms: D000028:Abortion, Induced / Q000706:statistics & numerical data; D015331:Cohort Studies; D019587:Dietary Supplements; D005060:Europe / Q000453:epidemiology; D005260:Female; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007557:Israel / Q000453:epidemiology; D009436:Neural Tube Defects / Q000453:epidemiology / Q000517:prevention & control*; D016742:Preconception Care; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D012042:Registries; D012189:Retrospective Studies
chemical_list: D005492:Folic Acid
references.citation: Am J Med Genet A. 2003 Dec 1;123A(2):123-8
references.pmid: 14598335
references.citation: Am J Med Genet C Semin Med Genet. 2004 Feb 15;125C(1):12-21
references.pmid: 14755429
references.citation: Scand J Public Health. 2004;32(4):264-71
references.pmid: 15370766
references.citation: Arch Dis Child. 1976 Dec;51(12):944-50
references.pmid: 1015847
references.citation: Lancet. 1980 Feb 16;1(8164):339-40
references.pmid: 6101792
references.citation: Lancet. 1983 May 7;1(8332):1027-31
references.pmid: 6133069
references.citation: Lancet. 1991 Jul 20;338(8760):131-7
references.pmid: 1677062
references.citation: N Engl J Med. 1992 Dec 24;327(26):1832-5
references.pmid: 1307234
references.citation: MMWR Morb Mortal Wkly Rep. 1998 Sep 25;47(37):773-8
references.pmid: 9769135
references.citation: Lancet. 2002 Dec 21-28;360(9350):2047-8
references.pmid: 12504403
references.citation: N Engl J Med. 1999 Nov 11;341(20):1485-90
references.pmid: 10559448
references.citation: N Engl J Med. 1999 Nov 11;341(20):1509-19
references.pmid: 10559453
references.citation: Acta Obstet Gynecol Scand. 2000 Jun;79(6):513-9
references.pmid: 10857878
references.citation: J Epidemiol Community Health. 2000 Sep;54(9):660-6
references.pmid: 10942444
references.citation: JAMA. 2001 Jun 20;285(23):2981-6
references.pmid: 11410096
references.citation: Ir Med J. 2001 Jun;94(6):180-1
references.pmid: 11495236
references.citation: J Nutr. 2002 Feb;132(2):289-91
references.pmid: 11823592
references.citation: BMJ. 2002 Jun 8;324(7350):1348-9
references.pmid: 12052788
references.citation: Prev Med. 2002 Jul;35(1):65-9
references.pmid: 12079442
references.citation: MMWR Morb Mortal Wkly Rep. 2002 Sep 13;51(36):808-10
references.pmid: 12269469