AneuploidyPregnancyMaternal Serum Screening TestsChromosomesTrisomyChromosomes, Human, Pair 18Down SyndromeChromosome MappingPrenatal DiagnosisChromosomes, Human, Pair 13Fetal DiseasesPregnancy Trimester, FirstFetusUltrasonography, PrenatalChromosome AberrationsNasal BoneX ChromosomeChromosome BandingChromosome SegregationSex ChromosomesChromosomes, HumanPregnancy Trimester, SecondNeckChromosomes, Human, Pair 1In Situ Hybridization, FluorescenceGenetic TestingKaryotypingChromosomes, Human, Pair 21Chromosomes, Human, Pair 7Chromosome DisordersChromosomes, Human, Pair 17Chromosomes, BacterialChromosomes, Human, Pair 11Gestational AgeChromosomes, Human, XChromosomes, Human, Pair 9Chromosomes, Human, YChromosome DeletionChromosomes, Human, Pair 6Chromosomes, PlantChromosomes, FungalChromosomes, MammalianChromosomal InstabilityChromosomes, Human, Pair 16Chromosomes, Human, Pair 8Chromosomes, Human, 6-12 and XChromosomes, Human, Pair 12Chromosomes, Human, Pair 22Chromosome PairingChromosomes, Human, Pair 2Chromosome PaintingChromosomes, Human, Pair 4Chromosomes, Human, Pair 10Chromosomes, Human, Pair 19Chromosomes, Artificial, BacterialChromosomes, Human, Pair 5Chromosomes, Human, 1-3MeiosisChromosomes, Human, Pair 20Chromosomes, Human, Pair 15Chromosome BreakageChromosomes, Human, Pair 14Chromosomes, Human, 21-22 and YMitosisChromosomes, Human, 16-18Chromosomes, Artificial, YeastPloidiesPreimplantation DiagnosisMetaphaseChromosomes, Human, 13-15Genetic LinkageGenetic MarkersMolecular Sequence DataDiploidyNondisjunction, GeneticMosaicismCentromereSensitivity and SpecificityBase SequenceTranslocation, GeneticPolymerase Chain ReactionPolyploidyRing ChromosomesChromosome InversionChromosome PositioningChromosomes, Human, 4-5Prospective StudiesSpindle ApparatusMutationKaryotypeX Chromosome InactivationPhenotypeSpermatozoa