title: Periconceptional folic acid use and the prevalence of neural tube defects in The Netherlands.
abstract: OBJECTIVE
  To study the effect of increased folic acid intake on the prevalence of neural tube defects (NTD) in The Netherlands.
  
  
  METHODS
  Using the capture-recapture method, the prevalence of NTD was estimated on the basis of five different registries on births affected by NTD.
  
  
  RESULTS
  Total prevalence over the 1988-1998 period varied between 1.43 and 1.96 per 1000 live and still births. No decrease in total prevalence was found to have taken place during that period. Scrutiny of the last 2 years, 1997 and 1998, in which increased folic acid intake might be expected to have had an effect, did not give any indication that the prevalence of NTD was falling.
  
  
  CONCLUSIONS
  A decrease in the Dutch prevalence of NTD during the study period could not be demonstrated due to the relatively small number of women using folic acid periconceptionally. This does not mean automatically that periconceptional folic acid use is ineffective in reducing the Dutch prevalence of NTD. Further monitoring is needed.
authors.affiliation: TNO Prevention and Health, P.O. Box 2215, 2301 CE Leiden, The Netherlands. km.vanderpal@pg.tno.nl
authors.forename: Karin M
authors.initials: KM
authors.lastname: van der Pal-de Bruin
authors.forename: Peter G M
authors.initials: PG
authors.lastname: van der Heijden
authors.forename: Simone E
authors.initials: SE
authors.lastname: Buitendijk
authors.forename: A Lya
authors.initials: AL
authors.lastname: den Ouden
mesh_terms: D019587:Dietary Supplements; D005260:Female; D005306:Fertilization; D005492:Folic Acid / Q000008:administration & dosage*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D009426:Netherlands / Q000453:epidemiology; D009436:Neural Tube Defects / Q000453:epidemiology* / Q000517:prevention & control; D011247:Pregnancy; D012042:Registries
chemical_list: D005492:Folic Acid