Yolk SacGestational SacEgg YolkPregnancy Trimester, FirstPregnancy, EctopicUltrasonography, PrenatalCrown-Rump LengthPregnancyExtraembryonic MembranesEndodermal Sinus TumorEmbryo, MammalianAbortion, SpontaneousAbortion, MissedEndolymphatic SacGestational AgeVitelline MembraneAir SacsAbortifacient Agents, NonsteroidalMesonephromaUltrasonographyChick EmbryoEmbryo, NonmammalianAnal SacsPregnancy TestsAbortion, IncompleteUterine HemorrhageEndodermEmbryonic and Fetal DevelopmentImaging, Three-DimensionalPregnancy OutcomeFetal DeathAmniotic FluidEmbryonic DevelopmentPregnancy, TubalHematopoiesis, ExtramedullaryGene Expression Regulation, DevelopmentalPregnancy, MultipleEmbryo LossEmbryo ImplantationFertilization in VitroChorionic Gonadotropin, beta Subunit, HumanBlastocystUltrasonicsSensitivity and SpecificityUltrasonic Therapyalpha-FetoproteinsPlacentaPinocytosisCicatrixProspective StudiesHigh-Intensity Focused Ultrasound AblationPovidoneFetusUltrasonography, InterventionalSperm Injections, IntracytoplasmicEgg ProteinsDysgerminomaPregnancy ComplicationsBlood VesselsHematopoietic Stem CellsAmnionMicrobubblesEmbryo TransferCell DifferentiationChorionic GonadotropinIn Situ HybridizationTeratomaHematopoiesisMesonephrosTime FactorsMesodermReproducibility of ResultsPredictive Value of TestsErythropoiesisMolecular Sequence DataCulture TechniquesTesticular NeoplasmsZebrafishGastrulaNeoplasms, Germ Cell and EmbryonalRNA, MessengerHematopoietic SystemPlacentationErythroblastsChimera