| 
      
        |  | Natera 
          Panorama | Verinata 
          Verifi | Sequenom    MaterniT21 PLUS | Ariosa 
          Harmony |  
        | Identified    Trisomies | 13, 18, 21 | 13, 18, 21,    sex chromosomes | 13, 18, 21,    sex chromosomes | 13, 18, 21,    sex chromosomes |  
        | Identified    Monosomies | X Chromosome | X Chromosome | X Chromosome | X Chromosome |  
        | Method | Single    Nucleotid Polymorphism | Massive    Parallel Sequencing | Massive    Parallel Sequencing | Selective    Sequencing |  
        | Sensitivity | 92-99% | 87-99% | 92-99% | 80-99% |  
        | Specificity    earlier | 100% | 100% | >99% | >99% |  
        | gestational    age | 9 w | 10 w | 10 w | 10 w |  |