Umbilical VeinsUmbilical ArteriesHernia, UmbilicalFetal BloodHuman Umbilical Vein Endothelial CellsUmbilicusEndothelium, VascularCord Blood Stem Cell TransplantationPregnancyUltrasonography, PrenatalCells, CulturedEndothelial CellsInfant, NewbornSingle Umbilical ArteryUltrasonography, DopplerGestational AgeFetal Growth RetardationPlacental CirculationFetusUrachal CystBlood Flow VelocityPlacentaHeart Rate, FetalFetal DiseasesMaternal-Fetal ExchangeFetal DistressFetal HypoxiaBlood BanksWharton JellyCell AdhesionNeovascularization, PhysiologicPulsatile FlowEndotheliumFetal MonitoringMesenchymal Stromal CellsUltrasonography, Doppler, PulsedPregnancy OutcomeUrachusApgar ScoreE-SelectinVascular Cell Adhesion Molecule-1Ultrasonography, Doppler, ColorCesarean SectionPregnancy Trimester, ThirdVascular Endothelial Growth Factor AAntigens, CD34Cell MovementFetal HeartRNA, MessengerIntercellular Adhesion Molecule-1Placental InsufficiencyPregnancy Trimester, SecondPre-EclampsiaCell ProliferationHematopoietic Stem CellsNitric Oxide Synthase Type IIITime FactorsAngiogenesis InhibitorsPregnancy Trimester, FirstNeovascularization, PathologicCell Culture TechniquesTumor Necrosis Factor-alphaAmniotic FluidAntigens, CDCell DifferentiationFetofetal TransfusionCoculture TechniquesCell Adhesion MoleculesFlow CytometryFetal DeathThrombinCulture Media, ConditionedSheepDose-Response Relationship, DrugChorionCatheterization, PeripheralInfant, Small for Gestational AgeSignal TransductionInfant, Newborn, DiseasesAnesthesia, ObstetricalUterusCell SurvivalRegional Blood FlowBirth WeightEpoprostenolPlacenta DiseasesCell SeparationCell DivisionNitric OxideFetal WeightStem CellsDelivery, ObstetricFetal MovementVascular Endothelial Growth Factor Receptor-2Gene Expression RegulationReverse Transcriptase Polymerase Chain Reactionvon Willebrand FactorCell LineAmnionProspective Studies