Umbilical ArteriesUltrasonography, DopplerUltrasonography, Doppler, ColorDoppler EffectBlood Flow VelocityUmbilical VeinsUltrasonography, Doppler, PulsedUltrasonographyUltrasonography, Doppler, TranscranialUltrasonography, PrenatalUltrasonicsPregnancyPulsatile FlowRegional Blood FlowEchocardiography, Doppler, ColorEchocardiography, Doppler, PulsedPlacental CirculationUltrasonography, InterventionalHernia, UmbilicalUltrasonic TherapySensitivity and SpecificityGestational AgeLaser-Doppler FlowmetryProspective StudiesImaging, Three-DimensionalHigh-Intensity Focused Ultrasound AblationFetal Growth RetardationMicrobubblesFetal DiseasesFetal BloodReproducibility of ResultsMiddle Cerebral ArteryPregnancy Trimester, SecondFetal MonitoringHeart Rate, FetalCerebrovascular CirculationEchoencephalographyVascular ResistanceObserver VariationUterusPredictive Value of TestsInfant, NewbornArteriesUltrasonography, Doppler, DuplexFetal HeartContrast MediaCerebral ArteriesUterine ArteryOphthalmic ArteryHuman Umbilical Vein Endothelial CellsFetusPregnancy Trimester, ThirdIntracranial Embolism and ThrombosisPortal VeinTransducersUmbilicusAdnexal DiseasesFemoral ArteryBlood PressureHemodynamicsPregnancy OutcomeEchocardiographyEndothelium, VascularPregnancy Trimester, FirstBrachial ArteryLegAngiographyCarotid StenosisTime FactorsMitral ValveEmbolism, AirCarotid Artery DiseasesIntracranial EmbolismForearmPlacenta DiseasesRheologyConstriction, PathologicArterial Occlusive DiseasesAdnexa UteriCardiac OutputFetal HypoxiaCarotid ArteriesReference ValuesHyperemiaPre-EclampsiaPlacentaUltrasonography, MammaryUterine HemorrhageFetal MovementImage Interpretation, Computer-AssistedSplenic ArteryValsalva ManeuverBlood CirculationCardiac CatheterizationRetrospective StudiesTreatment OutcomeCord Blood Stem Cell TransplantationFeasibility StudiesImage EnhancementPregnancy, High-Risk