Maternal AgeFathersPaternal AgeNondisjunction, GeneticTrisomyChromosomes, Human, 21-22 and YGenomic ImprintingPregnancyAbnormalities, MultipleKaryotypingX ChromosomeTranslocation, GeneticChromosome AberrationsMicrosatellite RepeatsChromosome DeletionPedigreeIn Situ Hybridization, FluorescenceDown SyndromeBirth OrderPregnancy, High-RiskInfant, NewbornAmniocentesisParityPregnancy OutcomeReplication OriginBirth WeightGestational AgePrenatal DiagnosisPregnancy Trimester, FirstPregnancy ComplicationsCongenital AbnormalitiesAbortion, SpontaneousAneuploidyBirth CertificatesCrown-Rump LengthNuchal Translucency MeasurementChromosome DisordersRisk FactorsCesarean SectionPregnancy Trimester, SecondInfant, Low Birth WeightUltrasonography, PrenatalInfant MortalityFetal DeathChorionic Gonadotropin, beta Subunit, HumanPregnancy, MultipleMothersPremature BirthPregnancy-Associated Plasma Protein-AHernia, UmbilicalGastroschisisPreimplantation DiagnosisPrenatal CareFertilization in VitroStillbirthLive BirthPerinatal MortalityBirth IntervalsReproductive Techniques, AssistedInfant, Small for Gestational AgeFetal DiseasesCohort StudiesPolar BodiesPregnancy in AdolescenceAbortion, EugenicChromosomes, Human, Pair 21Birth RateDelivery, ObstetricChorionic Villi SamplingTwinsLogistic ModelsObstetric Labor ComplicationsChromosomes, Human, Pair 18NeckRetrospective StudiesOdds RatioPrenatal Exposure Delayed EffectsMarital StatusRegistriesCase-Control StudiesSocioeconomic FactorsSex RatioChromosomes, Human, Pair 13Breast FeedingMaternal ExposureObstetric Labor, PrematurePre-EclampsiaProspective StudiesSperm Injections, IntracytoplasmicNasal BoneEducational StatusDiabetes, GestationalAge FactorsEmbryo TransferRegression AnalysisRiskOrigin Recognition ComplexNorwayAbortion, HabitualSicily