Maternal AgePregnancyPaternal AgeDown SyndromeBirth OrderPregnancy, High-RiskInfant, NewbornAmniocentesisParityPregnancy OutcomeBirth WeightGestational AgePrenatal DiagnosisTrisomyPregnancy Trimester, FirstPregnancy ComplicationsCongenital AbnormalitiesNondisjunction, GeneticAbortion, SpontaneousBirth CertificatesCrown-Rump LengthNuchal Translucency MeasurementAneuploidyChromosome DisordersRisk FactorsCesarean SectionPregnancy Trimester, SecondInfant, Low Birth WeightUltrasonography, PrenatalInfant MortalityChorionic Gonadotropin, beta Subunit, HumanPregnancy, MultipleFetal DeathPremature BirthMothersPregnancy-Associated Plasma Protein-AHernia, UmbilicalGastroschisisPreimplantation DiagnosisPrenatal CareFertilization in VitroLive BirthStillbirthPerinatal MortalityBirth IntervalsReproductive Techniques, AssistedInfant, Small for Gestational AgeFetal DiseasesAbortion, EugenicPregnancy in AdolescenceChromosome AberrationsPolar BodiesCohort StudiesDelivery, ObstetricBirth RateChromosomes, Human, Pair 21Chorionic Villi SamplingObstetric Labor ComplicationsTwinsLogistic ModelsChromosomes, Human, Pair 18Chromosomes, Human, 21-22 and YMarital StatusKaryotypingOdds RatioNeckPrenatal Exposure Delayed EffectsRegistriesSocioeconomic FactorsRetrospective StudiesCase-Control StudiesSex RatioBreast FeedingChromosomes, Human, Pair 13Maternal ExposureObstetric Labor, PrematurePre-EclampsiaSperm Injections, IntracytoplasmicNasal BoneDiabetes, GestationalProspective StudiesEducational StatusEmbryo TransferRegression AnalysisRiskAbortion, HabitualGravidityNorwayFetal MacrosomiaAge FactorsSicilyPregnancy Trimester, ThirdPregnancy, TwinMultiple Birth OffspringSocial ClassHypertension, Pregnancy-InducedDenmarkFetal Growth RetardationEstriolMeiosis