Table 2.
Identification of CNVs in different groups of NT measurement.
| NT (mm) | Numerical abnormalities of chromosomes | P/LP CNVs | VUS CNVs | Normal | Total | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Total | Trisomy-21 | Trisomy-18 | Trisomy-13 | monosomy-X | Other | |||||
| <2.5 | 2 (0.8) | 0 (0.0) | 1 (0.4) | 0 (0.0) | 0 (0.0) | 1 (0.4) | 3 (1.1) | 20 (7.6) | 237 (90.5) | 262 |
| 2.5–2.9 | 12 (4.1) | 8 (2.7) | 1 (0.3) | 1 (0.3) | 0 (0.0) | 2 (0.7) | 15 (5.1) | 24 (8.2) | 242 (82.6) | 293 |
| 3.0–3.4 | 42 (7.5) | 23 (4.1) | 7 (1.3) | 4 (0.7) | 3 (0.5) | 5 (0.9) | 29 (5.2) | 30 (5.4) | 457 (81.9) | 558 |
| 3.5–4.4 | 82 (13.6) | 49 (8.1) | 10 (1.7) | 6 (1.0) | 5 (0.8) | 12 (2.0) | 26 (4.3) | 43 (7.1) | 451 (74.9) | 602 |
| 4.5–5.4 | 42 (16.5) | 19 (7.5) | 9 (3.5) | 4 (1.6) | 5 (2.0) | 5 (2.0) | 22 (8.7) | 16 (6.3) | 174 (68.5) | 254 |
| 5.5–6.4 | 41 (32.0) | 14 (10.9) | 7 (5.5) | 4 (3.1) | 10 (7.8) | 6 (4.7) | 6 (4.7) | 6 (4.7) | 75 (58.6) | 128 |
| ≥6.5 | 90 (51.4) | 9 (5.1) | 27 (15.4) | 2 (1.1) | 51 (29.1) | 1 (0.6) | 13 (7.4) | 6 (3.4) | 66 (37.7) | 175 |
| Total | 311 (13.7) | 122 (5.4) | 62 (2.7) | 21 (0.9) | 74 (3.3) | 32 (1.4) | 114 (5.0) | 145 (6.4) | 1702 (74.9) | 2,272 |
| χ2 trend | 275.11 | 22.33 | 84.00 | – | 217.58 | – | 8.60 | 3.35 | 184.84 | |
| p-value | <0.0001 | <0.0001 | <0.0001 | – | <0.0001 | – | <0.05 | >0.05 | <0.0001 | |
P/LP CNVs, pathogenic/likely pathogenic copy number variations; VUS CNV, variant of uncertain significance copy number variations.