PregnancyGestational AgeFetusPregnancy, AnimalUltrasonography, PrenatalPregnancy Trimester, SecondPlacentaPregnancy Trimester, FirstInfant, NewbornPregnancy Trimester, ThirdMaternal-Fetal ExchangeFetal DevelopmentFetal DiseasesEmbryonic and Fetal DevelopmentPregnancy OutcomeBirth WeightInfant, PrematureFetal DeathLitter SizePregnancy ComplicationsLactationFetal WeightPrenatal Exposure Delayed EffectsUterusAmniotic FluidPremature BirthFetal HeartPregnancy, MultipleObstetric Labor, PrematureFetal Growth RetardationLabor, ObstetricMaternal Nutritional Physiological PhenomenaCrown-Rump LengthHeart Rate, FetalAnimals, NewbornTwinsPlacental CirculationSwineParityPrenatal DiagnosisFetal BloodPregnancy TrimestersPrenatal Nutritional Physiological PhenomenaBody WeightCesarean SectionPre-EclampsiaMaternal ExposureFetal Organ MaturityTrophoblastsOrgan SizePregnancy Complications, CardiovascularPostpartum PeriodAbortion, SpontaneousPregnancy, High-RiskAnimal Nutritional Physiological PhenomenaReproductionParturitionAmniocentesisExtraembryonic MembranesPregnancy, ProlongedProspective StudiesPlacentationTripletsAbortion, VeterinaryFetal ResorptionMyometriumChorionAbortion, InducedInfant, Small for Gestational AgePlacenta DiseasesViviparity, NonmammalianFetal ViabilityFetal HypoxiaLabor, InducedUmbilical ArteriesFetal Membranes, Premature RuptureStillbirthUmbilical CordInfant, Extremely PrematureAbnormalities, Drug-InducedFetal Nutrition DisordersHydrocortisonePregnancy in DiabeticsUterine ContractionAmnionPregnancy Complications, InfectiousDelivery, ObstetricFetal MonitoringChorionic Villi SamplingAnimal FeedChorioamnionitisBetamethasonePrenatal CarePregnancy ProteinsDown SyndromeAnimals, SucklingInfant, Low Birth WeightTime FactorsRandom AllocationEmbryo Implantation