Fetofetal TransfusionTwins, MonozygoticTwinsPregnancyDiseases in TwinsChorionPregnancy, MultipleTwins, DizygoticTwins, ConjoinedPregnancy OutcomePregnancy, TwinPregnancy Reduction, MultifetalUltrasonography, PrenatalPregnancy ComplicationsArteriovenous AnastomosisFetoscopyFetal DeathPregnancy Trimester, FirstGestational AgePregnancy, AnimalTripletsUmbilical ArteriesArterio-Arterial FistulaUmbilical CordPregnancy, EctopicPregnancy Trimester, SecondPlacentaPolyhydramniosTwin Studies as TopicPlacentationInfant, NewbornFetal Growth RetardationFetal DiseasesAmnionPregnancy Trimester, ThirdPregnancy RateNuchal Translucency MeasurementPregnancy, High-RiskLaser CoagulationOligohydramniosAmniocentesisLeg DermatosesAmniotic FluidPregnancy Complications, CardiovascularPregnancy TrimestersPregnancy TestsCrown-Rump LengthPregnancy, TripletPregnancy in DiabeticsPregnancy, TubalReproductive TechniquesQuintupletsPregnancy Complications, NeoplasticBirth WeightFetal DevelopmentPregnancy in AdolescencePregnancy Complications, InfectiousBlood Transfusion, IntrauterineReproductive Techniques, AssistedPrenatal DiagnosisAbortion, SpontaneousLeukomalacia, PeriventricularEchoencephalographyPregnancy ProteinsYolk SacSperm Injections, IntracytoplasmicPregnancy, UnplannedProspective StudiesPregnancy, UnwantedRetrospective StudiesPregnancy Complications, HematologicPre-EclampsiaPregnancy, ProlongedFetal BloodEmbryo TransferFertilization in VitroRisk FactorsAbortion, InducedUterusPregnancy, AbdominalBlood Flow VelocityCohort StudiesPregnancy Complications, ParasiticEmbryo ImplantationPregnancy MaintenancePrenatal CareParityHeart Defects, CongenitalMaternal AgeMaternal-Fetal ExchangeCesarean SectionPrenatal Exposure Delayed Effects