PregnancyVeinsPregnancy OutcomePregnancy ComplicationsPregnancy, AnimalSaphenous VeinPregnancy, EctopicPortal VeinVaricose VeinsPregnancy Trimester, FirstPregnancy Trimester, ThirdPregnancy RateFemoral VeinPregnancy Complications, CardiovascularPulmonary VeinsPregnancy TrimestersPregnancy TestsJugular VeinsPregnancy, MultiplePregnancy in DiabeticsPregnancy Trimester, SecondPregnancy, TubalPregnancy Complications, NeoplasticPregnancy in AdolescencePregnancy Complications, InfectiousMesenteric VeinsAbortion, SpontaneousUmbilical VeinsIliac VeinRenal VeinsPregnancy ProteinsPregnancy, UnplannedPregnancy, High-RiskPregnancy, UnwantedGestational AgeHepatic VeinsPopliteal VeinPregnancy Complications, HematologicInfant, NewbornPre-EclampsiaPlacentaPregnancy, ProlongedPregnancy, TwinFetal DeathSubclavian VeinSplenic VeinCerebral VeinsUterusAbortion, InducedUltrasonography, PrenatalPregnancy, AbdominalPregnancy Complications, ParasiticPregnancy MaintenanceEmbryo ImplantationEmbryo TransferPrenatal CareFertilization in VitroRetinal VeinMaternal-Fetal ExchangeAzygos VeinBrachiocephalic VeinsParityPrenatal Exposure Delayed EffectsBirth WeightAxillary VeinPregnancy Reduction, MultifetalRetinal Vein OcclusionCesarean SectionMaternal AgeHypertension, Pregnancy-InducedFetal Growth RetardationProgesteroneProspective StudiesPremature BirthFetusInfertility, FemaleLactationAbnormalities, Drug-InducedFetal DevelopmentLabor, ObstetricTime FactorsCongenital AbnormalitiesDeciduaObstetric Labor, PrematureTwinsPrenatal DiagnosisChorionic GonadotropinMaternal ExposureRisk FactorsFetal DiseasesDiabetes, GestationalRetrospective StudiesAbortion, TherapeuticTrophoblastsVenous ThrombosisPuerperal DisordersAbortion, HabitualAbortifacient Agents, NonsteroidalDelivery, ObstetricInsemination, Artificial