Neural Tube DefectsSpinal DysraphismSpina Bifida OccultaSpina Bifida CysticaAnencephalyNeural TubeMeningomyeloceleFolic AcidEncephalocelePregnancyNeurulationPrenatal DiagnosisPreconception CareVitamin B ComplexHydrocephalusCongenital AbnormalitiesAbortion, TherapeuticFourth VentricleFood, FortifiedInfant, NewbornFolic Acid Deficiencyalpha-FetoproteinsPrenatal CareNervous SystemFetal DeathDietary SupplementsAmniotic FluidNeural CrestAir Pollution, RadioactiveAmniocentesisMethylenetetrahydrofolate Dehydrogenase (NADP)Embryo, MammalianGene Expression Regulation, DevelopmentalHomocysteineCerebrospinal Fluid ShuntsFetal DiseasesPaired Box Transcription FactorsMethylenetetrahydrofolate Reductase (NADPH2)MeningoceleIrelandIndividuationMice, Mutant StrainsMouth AbnormalitiesGestational AgeCentral Nervous SystemEmbryonic and Fetal DevelopmentChick EmbryoFlourCase-Control StudiesVitamin B 12Pregnancy Trimester, FirstUltrasonography, PrenatalTailAbnormalities, MultipleZinebAbortion, InducedPregnancy ComplicationsAbnormalities, Drug-InducedMaternal ExposureBody PatterningIn Situ HybridizationVitamin B 12 DeficiencyPrevalenceUrinary Bladder, NeurogenicNotochordCaliforniaAbnormalities, Severe Teratoid5,10-Methylenetetrahydrofolate Reductase (FADH2)VitaminsMutationPregnancy in DiabeticsEmbryonic DevelopmentManebAbortion, SpontaneousAcrocallosal SyndromeLumbosacral RegionFormate-Tetrahydrofolate LigasePhenotypeRisk FactorsMorphogenesisThymidine MonophosphateDeanolTranscription FactorsTeratogensPollen TubeSpineCrown-Rump LengthFolate Receptor 1Prenatal Nutritional Physiological PhenomenaRiskArnold-Chiari MalformationHomozygoteTexasHeart Defects, CongenitalMaternal AgeGenotypeCell PolarityTetrahydrofolatesMethylenetetrahydrofolate Dehydrogenase (NAD+)Cleft Lip