Bed RestPregnancyHypertensionHead-Down TiltHypertension, PulmonaryWeightlessness SimulationPregnancy ComplicationsPregnancy OutcomeWeightlessness CountermeasuresRestPregnancy, AnimalCardiovascular DeconditioningPregnancy, EctopicSpace FlightBlood PressureBedsHypertension, RenalPregnancy Complications, CardiovascularHypertension, PortalPregnancy Trimester, FirstPregnancy Trimester, ThirdWeightlessnessPregnancy RateAntihypertensive AgentsHypertension, RenovascularPregnancy TrimestersPregnancy TestsPregnancy, MultipleOrthostatic IntolerancePregnancy in DiabeticsHypertension, MalignantHypertension, Pregnancy-InducedPregnancy Trimester, SecondPregnancy, TubalPregnancy Complications, NeoplasticTime FactorsPregnancy in AdolescenceLower Body Negative PressureRisk FactorsPregnancy Complications, InfectiousPre-EclampsiaAbortion, SpontaneousPregnancy ProteinsPregnancy, High-RiskGestational AgePregnancy, UnplannedPregnancy, UnwantedInfant, NewbornVascular ResistanceProspective StudiesPregnancy Complications, HematologicPlacentaReninHeart RateExercisePlasma VolumePulmonary ArteryHemodynamicsOcular HypertensionPregnancy, TwinBed OccupancyPregnancy, ProlongedSupine PositionTreatment OutcomeFetal DeathPrevalenceRats, Inbred SHRHypotension, OrthostaticUterusMuscle, SkeletalRetrospective StudiesCohort StudiesMuscular AtrophyBlood Pressure DeterminationKidneyIntracranial HypertensionFollow-Up StudiesAbortion, InducedEarly AmbulationPregnancy Complications, ParasiticPregnancy, AbdominalBody WeightUltrasonography, PrenatalPregnancy MaintenancePrenatal Exposure Delayed EffectsRats, Inbred WKYPrenatal CareReference ValuesEmbryo ImplantationBirth WeightParityEmbryo TransferFertilization in VitroDesoxycorticosteroneMaternal-Fetal ExchangeHypovolemiaAldosteroneAnalysis of VarianceRegional Blood FlowSodium Chloride, Dietary