Table 2.
Summary of abnormal NIPT results, confirmation and outcome
| MA (years) | GA | Prior risk | NIPT | FF (%) | NIPT risk score | Confirmatory invasive test | TP/FP | Outcome | |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 23 | 14w4d | 1:68 risk on combined screening | T21 | 9.2 | >99/100 | Amniocentesis | TP | Terminated |
| 2 | 34 | 17w | 1:50 risk on quadruple screening | T21 | 6.4 | >99/100 | Amniocentesis | TP | Terminated |
| 3 | 30 | 12w3d | 1:157 risk on combined screening | T21 | 12.9 | >99/100 | Not performed | NA | IUD at 24 weeks |
| 4 | 34 | 13w | 1:50 risk on combined screening | T21 | 14.7 | >99/100 | CVS | TP | Terminated |
| 5 | 37 | 13w3d | 1:48 risk on combined screening. | T21 | 6.9 | >99/100 | Not performed | NA | Terminated |
| 6 | 35 | 12w3d | 1:160 risk on combined screening | T21 | 10.1 | >99/100 | Amniocentesis | TP | Terminated |
| 7 | 24 | 15w1d | 1:8 risk on combined screening | T21 | 14.4 | >99/100 | CVS | TP | Terminated |
| 8 | 38 | 17w2d | 1:55 risk on triple screening | T21 | 6.9 | >99/100 | Amniocentesis | FP | Term delivery, normal baby |
| 9 | 24 | 14w3d | 1:115 risk on combined screening | MX | 8.0 | >99/100 | Amniocentesis | *TP | Terminated |
| 10 | 30 | 13w4d | 1:90 risk on combined screening | MX | 9.1 | >99/100 | Amniocentesis | TP | Terminated |
| 11 | 28 | 17w | 1:318 risk on quadruple screening | T21 | 15.5 | >99/100 | Amniocentesis | TP | Terminated |
| 12 | 38 | 15w4d | 1:1250 risk on combined screening | Suggestive XXY | 10.7 | – | Amniocentesis | FP | Term delivery, normal baby |
| 13 | 36 | 15w1d | 1:82 Biochemical risk (T13/18–1:371) | T21 | 7.8 | >99/100 | Amniocentesis | TP | Terminated |
| 14 | 32 | 12w2d | 1:1065 on combined screening | T21 | 4.7 | >83/100 | Amniocentesis | FP | Term delivery, normal baby |
| 15 | 42 | 14w6d | 1:199 risk on combined screening | Suggestive XXX | 9.0 | – | Amniocentesis | TP | Term delivery |
| 16 | 38 | 14w2d | 1:729 risk on combined screening | T21 | 4.6 | >99/100 | Amniocentesis | TP | Terminated |
| 17 | 31 | 13w5d | 1/329 risk on combined screening | T13 | 9.4 | >99/100 | Amniocentesis | TP | Terminated |
| 18 | 24 | 12w3d | 1:50 risk on combined screening | T21 | 9.9 | >99/100 | Not performed | NA | Terminated |
| 19 | 25 | 16w5d | >1:50 risk on combined screening | T18 | 4.4 | >99/100 | Amniocentesis | TP | Terminated |
MA—maternal age at expected date of delivery; GA—gestational age represented in weeks and days; prior risk refers to the risk on combined screening, triple screening or quadruple screening; IUD—intrauterine death, MX—monosomy X, *Isochromosome X with deletion of p arm was noted on karyotyping, which is a variant of Turner syndrome. Confirmation of the NIPT result was performed by fluorescence in situ hybridization followed by karyotyping or Karyolite BOBS (sample 12) after either amniocentesis or chorionic villus sampling (CVS) (sample 4 and 7). TP—true positive, FP—false positive, N.A—not available. The aneuploidy risk score of Sample 12 and 14 was lower than < 1000, but the samples were still included in the study