Fetal HeartHeart Rate, FetalFetusHeartFetal MonitoringCardiotocographyUltrasonography, PrenatalPregnancyHeart RateFetal DiseasesGestational AgeHeart Defects, CongenitalEchocardiography, Four-DimensionalFetal MovementFetal HypoxiaFetal DistressUmbilical ArteriesPregnancy Trimester, SecondHeart FailureCampylobacter fetusHeart BlockPregnancy Trimester, ThirdPregnancy Trimester, FirstUltrasonography, DopplerCanrenoic AcidMaternal-Fetal ExchangeTritrichomonas foetusEchocardiography, Three-DimensionalMagnetocardiographyPrenatal DiagnosisHeart DiseasesFetal DevelopmentLabor, ObstetricHeart TransplantationHeart ValvesFetal Growth RetardationSheepMyocardiumCardiac VolumeInfant, NewbornBradycardiaCrown-Rump LengthBlood Flow VelocityEchocardiographyAbortion, ThreatenedPregnancy OutcomeFetal DeathEmbryonic and Fetal DevelopmentPregnancy ComplicationsApgar ScoreProspective StudiesPlacentaDown SyndromeEchocardiography, Doppler, ColorHeart AtriaPlacental CirculationPregnancy, High-RiskMyocytes, CardiacHydrops FetalisFetal WeightUmbilical CordHemodynamicsPerinatologyMyocardial ContractionAmniotic FluidSheep, DomesticHeart SeptumNuchal Translucency MeasurementElectronics, MedicalAnalgesia, ObstetricalCesarean SectionAnesthesia, ObstetricalSensitivity and SpecificityChromosome DisordersUltrasonography, Doppler, ColorTocolytic AgentsPregnancy in DiabeticsCardiomegalyTime FactorsTrisomyUltrasonographyHeart AuscultationHeart Arrest, InducedReference ValuesFetal BloodFeasibility StudiesReproducibility of ResultsHeart Function TestsSufentanilPulsatile FlowMeconiumEchocardiography, DopplerDelivery, ObstetricHeart VentriclesNeckTachycardiaPregnancy, AnimalBlood Gas AnalysisMyocardial IschemiaAbortion, Spontaneous