Bed RestPregnancyHead-Down TiltWeightlessness SimulationPregnancy OutcomePregnancy ComplicationsWeightlessness CountermeasuresRestPregnancy, AnimalCardiovascular DeconditioningPregnancy, EctopicSpace FlightBedsPregnancy Trimester, FirstWeightlessnessPregnancy RatePregnancy Trimester, ThirdPregnancy Complications, CardiovascularPregnancy TrimestersPregnancy TestsPregnancy, MultipleOrthostatic IntolerancePregnancy in DiabeticsPregnancy, TubalPregnancy Trimester, SecondPregnancy Complications, NeoplasticPregnancy in AdolescenceLower Body Negative PressurePregnancy Complications, InfectiousAbortion, SpontaneousPregnancy, UnplannedPregnancy ProteinsPregnancy, High-RiskPregnancy, UnwantedGestational AgeTime FactorsInfant, NewbornPregnancy Complications, HematologicPlacentaPre-EclampsiaBed OccupancyPregnancy, TwinPregnancy, ProlongedPlasma VolumeFetal DeathSupine PositionExerciseMuscular AtrophyAbortion, InducedMuscle, SkeletalUterusEarly AmbulationPregnancy Complications, ParasiticPregnancy, AbdominalPregnancy MaintenanceUltrasonography, PrenatalEmbryo ImplantationHypotension, OrthostaticPrenatal CareEmbryo TransferFertilization in VitroParityMaternal-Fetal ExchangeHypovolemiaProspective StudiesVascular CapacitancePrenatal Exposure Delayed EffectsBirth WeightUterine Cervical IncompetenceAbortion, ThreatenedAmino Acids, EssentialImmobilizationCesarean Section