Pregnancy ComplicationsPregnancyPregnancy OutcomePre-EclampsiaHypertension, Pregnancy-InducedPregnancy Complications, CardiovascularPregnancy Complications, HematologicFemale Urogenital Diseases and Pregnancy ComplicationsPregnancy Trimester, FirstPregnancy, EctopicAbortion, SpontaneousPregnancy Complications, NeoplasticFetal Growth RetardationAbruptio PlacentaePremature BirthPregnancy, AnimalPlacentaPregnancy Trimester, SecondUterine ArteryPregnancy Trimester, ThirdPostoperative ComplicationsCivil DisordersPlacenta DiseasesPregnancy Complications, InfectiousEclampsiaObstetric Labor, PrematurePregnancy, TwinInfant, NewbornGestational AgePlacental CirculationCongenital AbnormalitiesTrophoblastsFetal DeathDiabetes, GestationalPreconception CarePregnancy, High-RiskPregnancy, MultipleCesarean SectionObstetric Labor ComplicationsUltrasonography, PrenatalStillbirthPrenatal CareUterusInfant, Small for Gestational AgeRisk FactorsAbortion, HabitualPregnancy ProteinsBirth WeightPregnancy RateRetrospective StudiesMaternal AgeParityAntibodies, AntiphospholipidPlacental InsufficiencyPregnancy TrimestersPlacentationProspective StudiesMultiple Birth OffspringPregnancy TestsDelivery, ObstetricMaternal-Fetal ExchangePregnancy in DiabeticsPregnancy, TubalAntiphospholipid SyndromeFetal DevelopmentMaternal WelfareReproductive Techniques, AssistedInfant, Low Birth WeightFertilization in VitroFetal Membranes, Premature RuptureCohort StudiesPregnancy in AdolescenceOdds RatioDeciduaTreatment OutcomeThrombophiliaLogistic ModelsRisk AssessmentPhysical ExaminationPregnancy, UnplannedPregnancy, UnwantedIntraoperative ComplicationsHomocysteineIncidenceTime FactorsNorwayUnited StatesInfant, PrematurePregnancy Complications, ParasiticFollow-Up StudiesPrevalenceQuestionnairesPregnancy, ProlongedCase-Control StudiesAbortion, InducedConfidence IntervalsPregnancy, AbdominalBiological MarkersEmbryo ImplantationPregnancy Maintenance