Ultrasonography, PrenatalUltrasonographyUltrasonography, Doppler, ColorPrenatal DiagnosisPrenatal Exposure Delayed EffectsUltrasonography, DopplerPrenatal CarePregnancyEndosonographyUltrasonography, Doppler, DuplexUltrasonography, Doppler, PulsedUltrasonography, MammaryFetal DiseasesUltrasonography, InterventionalSensitivity and SpecificityUltrasonography, Doppler, TranscranialProspective StudiesSulfur HexafluorideGestational AgeInfant, NewbornTomography, X-Ray ComputedContrast MediaUrographyPredictive Value of TestsReproducibility of ResultsRetrospective StudiesImaging, Three-DimensionalScrotumBlood Flow VelocityAmniocentesisFetusPregnancy Trimester, SecondCystsMagnetic Resonance ImagingHydronephrosisEchoencephalographyPalpationCarotid Artery DiseasesAbdomenPregnancy Trimester, ThirdChorionic Villi SamplingPregnancy OutcomePreoperative CareOvarian CystsToe JointThyroid NoduleAbortion, EugenicMaternal ExposureVaginaCarotid ArteriesGallbladderFollow-Up StudiesPregnancy Trimester, FirstMetacarpophalangeal JointPregnancy ComplicationsRisk FactorsLiver NeoplasmsObserver VariationImage EnhancementAbdominal InjuriesSplenic DiseasesTesticular DiseasesFetal DevelopmentDiagnostic ImagingFetal HeartCongenital AbnormalitiesFalse Positive ReactionsAuscultationTreatment OutcomeGallbladder DiseasesAngiographyRectumLymphangioma, CysticCarotid Artery, CommonTransducersBiliary Tract Diseases