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, ThirdCivil DisordersPostoperative ComplicationsPlacenta DiseasesPregnancy Complications, InfectiousEclampsiaPregnancy, TwinObstetric Labor, PrematureInfant, NewbornGestational AgePlacental CirculationTrophoblastsCongenital AbnormalitiesDiabetes, GestationalFetal DeathPreconception CarePregnancy, High-RiskPregnancy, MultipleCesarean SectionObstetric Labor ComplicationsStillbirthPrenatal CareUterusInfant, Small for Gestational AgeAbortion, HabitualUltrasonography, PrenatalPregnancy ProteinsBirth WeightRisk FactorsPregnancy RateMaternal AgeRetrospective StudiesParityAntibodies, AntiphospholipidPlacental InsufficiencyPregnancy TrimestersPlacentationMultiple Birth OffspringPregnancy TestsMaternal-Fetal ExchangeDelivery, ObstetricProspective StudiesPregnancy in DiabeticsToxicity TestsPregnancy, TubalAntiphospholipid SyndromeFetal DevelopmentMaternal WelfareReproductive Techniques, AssistedTreatment OutcomeInfant, Low Birth WeightFetal Membranes, Premature RuptureFertilization in VitroPregnancy in AdolescenceCohort StudiesDeciduaOdds RatioThrombophiliaRisk AssessmentLogistic ModelsPregnancy, UnplannedPregnancy, UnwantedTime FactorsIntraoperative ComplicationsHomocysteineIncidenceNorwayInfant, PrematurePregnancy Complications, ParasiticToxicity Tests, AcutePregnancy, ProlongedUnited StatesFollow-Up StudiesCase-Control StudiesAbortion, InducedQuestionnairesConfidence IntervalsPrevalencePregnancy, AbdominalEmbryo ImplantationPregnancy Maintenance