Anemia, MegaloblasticAnemia, MacrocyticVitamin B 12 DeficiencyFolic Acid DeficiencyMegaloblastsAnemia, PerniciousVitamin B 12ThiamineFIGLU TestHydroxocobalaminAnemiaIntrinsic FactorFolic AcidPregnancy Complications, HematologicAnemia, HypochromicHomocystinuriaDeoxyuridineBone Marrow Examination5-Methyltetrahydrofolate-Homocysteine S-MethyltransferaseMalabsorption SyndromesVitamin B ComplexDiphyllobothriasisSchilling TestTranscobalaminsPancytopeniaHearing Loss, SensorineuralAnemia, AplasticBlood Group AntigensMethylmalonic AcidConsanguinityErythropoiesisMembrane Transport ProteinsBloodBone Marrow